Hokay, here's the deal. My friends and I make t-shirts. We make t-shirts a lot. I have in the past made t-shirts that look like this and this and this. I've learned through making mistakes and I feel pretty confident in my skill level at this point to do what I want to do. Which means that when
paper_tzipporah asked how to put a TARDIS on something I thought 'I'VE GOT THIS, BRO.'
[Step 1: Supplies] If you want to do this project with any sort of quickness, it's best to start out with all of your supplies in one place.

A short list of things you'll need:
1. Your t-shirt. (Or scarf, or neck tie, or purse, or whatever you're painting on.)
2. Freezer paper. (It's important that it's wax on one side and paper on the other.)
2-Alternate. Card stock.
3. Scissors or an exacto knife. (The exacto knife will be better for most projects.)
4. Paint brushes or sponges.
5. Pencils and erasers if you're freehanding stencils.
6. Paint (I use both acrylic and fabric paint, but it's up to you.)
7. Something to hold the paint, we use little plastic cups.
8. An iron. (If you're using freezer paper.)
9. Cardboard scraps.
10. Tape (Optional.)
11. Fine sandpaper. (Optional.)
[Step 2: Prepping the Shirt] Depending on what kind of garment you're using and where you have it placed, you are going to want to place something thick that you're not worried about damaging between the surface you're painting and the surface beneath it. I use scrap pieces of cardboard. Just slide them into the shirt and place them in the area you're going to be painting on. We sometimes tape the shirts around the cardboard, but that's not really necessary unless it's imperative you be able to pull the fabric tight.

[Step 3: The Stencil] The stencil is what you're going to use as the guide for your paint. There are several ways to go about creating stencils. I'm going to talk about my two preferred methods.And then throw them out the window because I free handed this one.

From here on out I'm going to refer to your design in terms of positive and negative space. Positive space is your design, and the space on the shirt you want to paint. Negative space is your stencil, and the spaces on your shirt you don't want to paint.
Stencil Type the First - Card stock.
When I first started doing t-shirts I started out by making stencils with computer paper. I quickly realized that the paint bled through computer paper and caused a mess and started using card stock instead. The easiest way to make a card stock stencil is to create your image on the computer, printing it onto the card stock, and then carefully cutting the image out. The words on the Magneto t-shirt in the intro were done in this manner. That's why you need an exacto knife over scissors if you're doing a precise image. You want to be able to simply cut around the positive space of your image, leaving the negative space intact as the stencil.
(Pro tip: To cut out your stencils, place the stencil against a hard surface you're not afraid of marring to cut into it. I use the backs of spiral bound notebooks, because they're thick cardboard you can't make deep cuts in, but anything hard and flat will work.)
Once you get a card stock stencil cut, you then decide where on the garment the stencil is going, tape it down, and carefully paint in your positive space. This is where card stock stencils can get tricky. If you have an image that is a large amount of positive space with small amounts of negative space inside (and even smaller amounts of positive space inside of the negative space, like say, the windows on the TARDIS), you're going to have to cut out your negative spaces and tape them in place in such a manner that won't break up the positive space. To get a visual of what I'm talking about, look at the As and Rs on the Magneto shirt. I had to separately cut out the triangles in the As and insides of the Rs, place a piece of double sided tape (or a rolled of up piece of single sided tape) on the bottom and paste it into place so you can paint over it.
THIS IS THE HARDEST PART OF THE PROCESS. I PROMISE. Stencils are the most time consuming thing about the way I do this. There are probably other people who have fancy ways of doing it or like, screen printers? But I am not one of them, alas. I don't really think about it anymore, since I've done this a lot and I'm pretty quick at the whole thing. Practice makes perfect.
Stencil Type the Second - Freezer paper.
Freezer paper was a REVELATION. Depending on what you're doing you may still need to print your desired stencil onto computer paper and then trace it onto the freezer paper, but it will make things easy in the painting. The important thing to remember is that you want your stencil to be the right way round on the PAPER side of the freezer paper. You're going to then cut it out with an exacto knife the same way you cut the card stock. The upside is, once you get it cut out you are going to lay it where you want it on your garment and then iron it down using the iron. Do this slowly and press down on the stencil, making sure that the edges of it are stuck fast to your garment. Do not worry about damaging the garment, you won't. After you've done your painting and allowed it to dry you can pull up the freezer paper and dispose of it, no fuss.
The great upside to freezer paper, and why it was such a revelation, is that if you've ironed it down all the way you don't have to be extra careful laying the paint down, because it won't seep under your stencil and ruin your line. The other good thing about it is that if you do have hanging or floating pieces of negative space to paste in, you don't have to fuss with tape or be careful around those either. Just iron them into place and go.

Stencil Type the Third - Free hand!
Recently I've gotten farther and farther away from printing things off of the computer and being precise about them. Except for words. I still need stencils for letters. Though your need for a particular type of stencil will greatly depends on your skill level and the effect you're going for.
barbed_whispers free hands her letters just fine. There are a couple different ways to free hand. You can free hand onto paper and then cut it out as a stencil, as I did for the mushroom cloud shirt and the Nighting bird symbol shirt, or you can free hand directly onto the t-shirt, which is what I did for the Robin/Nightwing/Batman shirt and the Winter Soldier shirt.
In the case of this shirt I'm making in the tutorial I free handed onto the freezer paper and ironed it in place.

[Step 4: Painting] The tool you use for painting depends on what sort of visual effect you're going for and how comfortable you are putting paint onto the stencil. For this one I outlined the stencil using an actual medium sized brush, just so I'd have to be careful about getting paint outside of the lines. If you're using a card stock stencil you are going to want to paint with strokes that either go lightly along the length of the stencil, or outside in. You will want to avoid pushing paint out toward the stencil, because it's not sealed to the shirt and the paint will seep and blotch and mar your design.

For larger areas, or for iron on stencils you're comfortable with, you may want to use sponge brushes.

It's still a good idea to work down the length of the stencil or outside in, but you don't need to be too worried about it too much. I've also been known to use larger sponges on smaller stencils for textured paint effects, like below. THE SKY IS THE LIMIT, GUYS. THIS IS WHY I MAKE MY OWN SHIRTS.

(Pro tip: The kind of paint you use will affect what happens to the garment down the line. If it's something like a neck tie or a purse that won't get washed often, it doesn't really matter whether you use acrylic paints or fabric paints. If it's a shirt or a scarf or something that might get regular washings, acrylic paint will chip and crack over time. That's not a thing that I worry about, and I tend to use acrylic paints on everything because I kind of like things that look used, but Lisa prefers fabric paints.)
(Pro pro tip: The AMOUNT of paint you use will affect the wear of the garment. The Winter Soldier shirt has too much paint on it. I layered too many colors, which makes it really stiff and difficult to wear. If you are going to put one color over another and they both have large coverage areas, consider working them around each other instead of over. Anything more than two layers gets pretty clunky.)
[Step 5: Leave That Shit Alone] Go take a nap or a jog or something. Let the base coats dry.

[Step 6: Remove the Stencil and Assess Your Work] If you've used a card stock stencil you may need to pick bits of paper off your shirt. This is fine. If you don't need to paint over those areas with anything else you can throw it into the wash and the paper will come off. If you've used freezer paper, just pull it up and make sure your lines look like you want them to.
When I removed my stencil here I decided to add in the lines for the "feathers", so I took a smaller paint brush and outlined the area in a way that is reminiscent of Dick's costume. I free handed all of this, which you can tell, because I'm not patient and can't do straight lines to save my life.Or straight anything, really. But if you want to do something like this and aren't feeling confident enough to freehand it, then you can make another stencil, lay it over the first layer, and get back to work.

[Step 7: SUCCESS!] CONGRATS! YOU'VE NOW MADE YOUR OWN T-SHIRT DESIGN AND YOU DIDN'T EVEN HAVE TO PAY REDBUBBLE $20 FOR IT. If you have used a lot of paint you might have cardboard stuck to the underside of your garment along with bits of paper stencil stuck to the top. Like I mentioned earlier, throwing it in the wash should take care of this. If you are concerned with how 'rough' your finished paint is, use a piece of fine sandpaper to sand down over your design. Don't press too hard, you don't want to remove the paint, you just want to take that plastic-y edge off the finish and make it softer.
Once you've worked through these steps you should have something close to what you were aiming for. Don't beat yourself up if it's not perfect. No one is perfect. But you'll get better over time with practice, and since this a is a fun and creative little hobby, practice shouldn't be hard to come by.

I do want to say here that I don't consider myself a person with any sort of innate artistic sense or talent. I can't draw or paint or work digital design or any of those things that would get a shirt picked up at Threadless or whatever. What I can do is work with simple, kitschy designs, and I really believe anyone can do that. Don't be put off by your perceived artistic talent. Not that this process in the right, talented hands couldn't net you some really cool things (see Lisa's really cool Ravenclaw Quidditch shirt), but that's not what this is about. This is about wearing your ridiculous obsessions on your sleeve.
And that's that. It is really late right now and I have to get up really early in the morning to go to Tennessee, so I apologize for any typos, misspellings, or confusing statements. Please feel free to ask any questions in the comments. I know enough people who do this frequently enough that if I'm not here to answer you're liable to get one anyway.
Most importantly, have fun!
[Step 1: Supplies] If you want to do this project with any sort of quickness, it's best to start out with all of your supplies in one place.

A short list of things you'll need:
1. Your t-shirt. (Or scarf, or neck tie, or purse, or whatever you're painting on.)
2. Freezer paper. (It's important that it's wax on one side and paper on the other.)
2-Alternate. Card stock.
3. Scissors or an exacto knife. (The exacto knife will be better for most projects.)
4. Paint brushes or sponges.
5. Pencils and erasers if you're freehanding stencils.
6. Paint (I use both acrylic and fabric paint, but it's up to you.)
7. Something to hold the paint, we use little plastic cups.
8. An iron. (If you're using freezer paper.)
9. Cardboard scraps.
10. Tape (Optional.)
11. Fine sandpaper. (Optional.)
[Step 2: Prepping the Shirt] Depending on what kind of garment you're using and where you have it placed, you are going to want to place something thick that you're not worried about damaging between the surface you're painting and the surface beneath it. I use scrap pieces of cardboard. Just slide them into the shirt and place them in the area you're going to be painting on. We sometimes tape the shirts around the cardboard, but that's not really necessary unless it's imperative you be able to pull the fabric tight.

[Step 3: The Stencil] The stencil is what you're going to use as the guide for your paint. There are several ways to go about creating stencils. I'm going to talk about my two preferred methods.

From here on out I'm going to refer to your design in terms of positive and negative space. Positive space is your design, and the space on the shirt you want to paint. Negative space is your stencil, and the spaces on your shirt you don't want to paint.
Stencil Type the First - Card stock.
When I first started doing t-shirts I started out by making stencils with computer paper. I quickly realized that the paint bled through computer paper and caused a mess and started using card stock instead. The easiest way to make a card stock stencil is to create your image on the computer, printing it onto the card stock, and then carefully cutting the image out. The words on the Magneto t-shirt in the intro were done in this manner. That's why you need an exacto knife over scissors if you're doing a precise image. You want to be able to simply cut around the positive space of your image, leaving the negative space intact as the stencil.
(Pro tip: To cut out your stencils, place the stencil against a hard surface you're not afraid of marring to cut into it. I use the backs of spiral bound notebooks, because they're thick cardboard you can't make deep cuts in, but anything hard and flat will work.)
Once you get a card stock stencil cut, you then decide where on the garment the stencil is going, tape it down, and carefully paint in your positive space. This is where card stock stencils can get tricky. If you have an image that is a large amount of positive space with small amounts of negative space inside (and even smaller amounts of positive space inside of the negative space, like say, the windows on the TARDIS), you're going to have to cut out your negative spaces and tape them in place in such a manner that won't break up the positive space. To get a visual of what I'm talking about, look at the As and Rs on the Magneto shirt. I had to separately cut out the triangles in the As and insides of the Rs, place a piece of double sided tape (or a rolled of up piece of single sided tape) on the bottom and paste it into place so you can paint over it.
THIS IS THE HARDEST PART OF THE PROCESS. I PROMISE. Stencils are the most time consuming thing about the way I do this. There are probably other people who have fancy ways of doing it or like, screen printers? But I am not one of them, alas. I don't really think about it anymore, since I've done this a lot and I'm pretty quick at the whole thing. Practice makes perfect.
Stencil Type the Second - Freezer paper.
Freezer paper was a REVELATION. Depending on what you're doing you may still need to print your desired stencil onto computer paper and then trace it onto the freezer paper, but it will make things easy in the painting. The important thing to remember is that you want your stencil to be the right way round on the PAPER side of the freezer paper. You're going to then cut it out with an exacto knife the same way you cut the card stock. The upside is, once you get it cut out you are going to lay it where you want it on your garment and then iron it down using the iron. Do this slowly and press down on the stencil, making sure that the edges of it are stuck fast to your garment. Do not worry about damaging the garment, you won't. After you've done your painting and allowed it to dry you can pull up the freezer paper and dispose of it, no fuss.
The great upside to freezer paper, and why it was such a revelation, is that if you've ironed it down all the way you don't have to be extra careful laying the paint down, because it won't seep under your stencil and ruin your line. The other good thing about it is that if you do have hanging or floating pieces of negative space to paste in, you don't have to fuss with tape or be careful around those either. Just iron them into place and go.

Stencil Type the Third - Free hand!
Recently I've gotten farther and farther away from printing things off of the computer and being precise about them. Except for words. I still need stencils for letters. Though your need for a particular type of stencil will greatly depends on your skill level and the effect you're going for.
In the case of this shirt I'm making in the tutorial I free handed onto the freezer paper and ironed it in place.

[Step 4: Painting] The tool you use for painting depends on what sort of visual effect you're going for and how comfortable you are putting paint onto the stencil. For this one I outlined the stencil using an actual medium sized brush, just so I'd have to be careful about getting paint outside of the lines. If you're using a card stock stencil you are going to want to paint with strokes that either go lightly along the length of the stencil, or outside in. You will want to avoid pushing paint out toward the stencil, because it's not sealed to the shirt and the paint will seep and blotch and mar your design.

For larger areas, or for iron on stencils you're comfortable with, you may want to use sponge brushes.

It's still a good idea to work down the length of the stencil or outside in, but you don't need to be too worried about it too much. I've also been known to use larger sponges on smaller stencils for textured paint effects, like below. THE SKY IS THE LIMIT, GUYS. THIS IS WHY I MAKE MY OWN SHIRTS.

(Pro tip: The kind of paint you use will affect what happens to the garment down the line. If it's something like a neck tie or a purse that won't get washed often, it doesn't really matter whether you use acrylic paints or fabric paints. If it's a shirt or a scarf or something that might get regular washings, acrylic paint will chip and crack over time. That's not a thing that I worry about, and I tend to use acrylic paints on everything because I kind of like things that look used, but Lisa prefers fabric paints.)
(Pro pro tip: The AMOUNT of paint you use will affect the wear of the garment. The Winter Soldier shirt has too much paint on it. I layered too many colors, which makes it really stiff and difficult to wear. If you are going to put one color over another and they both have large coverage areas, consider working them around each other instead of over. Anything more than two layers gets pretty clunky.)
[Step 5: Leave That Shit Alone] Go take a nap or a jog or something. Let the base coats dry.

[Step 6: Remove the Stencil and Assess Your Work] If you've used a card stock stencil you may need to pick bits of paper off your shirt. This is fine. If you don't need to paint over those areas with anything else you can throw it into the wash and the paper will come off. If you've used freezer paper, just pull it up and make sure your lines look like you want them to.
When I removed my stencil here I decided to add in the lines for the "feathers", so I took a smaller paint brush and outlined the area in a way that is reminiscent of Dick's costume. I free handed all of this, which you can tell, because I'm not patient and can't do straight lines to save my life.

[Step 7: SUCCESS!] CONGRATS! YOU'VE NOW MADE YOUR OWN T-SHIRT DESIGN AND YOU DIDN'T EVEN HAVE TO PAY REDBUBBLE $20 FOR IT. If you have used a lot of paint you might have cardboard stuck to the underside of your garment along with bits of paper stencil stuck to the top. Like I mentioned earlier, throwing it in the wash should take care of this. If you are concerned with how 'rough' your finished paint is, use a piece of fine sandpaper to sand down over your design. Don't press too hard, you don't want to remove the paint, you just want to take that plastic-y edge off the finish and make it softer.
Once you've worked through these steps you should have something close to what you were aiming for. Don't beat yourself up if it's not perfect. No one is perfect. But you'll get better over time with practice, and since this a is a fun and creative little hobby, practice shouldn't be hard to come by.

I do want to say here that I don't consider myself a person with any sort of innate artistic sense or talent. I can't draw or paint or work digital design or any of those things that would get a shirt picked up at Threadless or whatever. What I can do is work with simple, kitschy designs, and I really believe anyone can do that. Don't be put off by your perceived artistic talent. Not that this process in the right, talented hands couldn't net you some really cool things (see Lisa's really cool Ravenclaw Quidditch shirt), but that's not what this is about. This is about wearing your ridiculous obsessions on your sleeve.
And that's that. It is really late right now and I have to get up really early in the morning to go to Tennessee, so I apologize for any typos, misspellings, or confusing statements. Please feel free to ask any questions in the comments. I know enough people who do this frequently enough that if I'm not here to answer you're liable to get one anyway.
Most importantly, have fun!
no subject
Date: 2012-12-21 06:40 am (UTC)/missss
I never can get the knife to cut out my stencils right. I have stoopid hands.
no subject
Date: 2012-12-22 04:17 am (UTC)And I also have stupid hands. But if you do it a lot you can sort of train your hands to work the way you need them to in that situation. Um, not in any OTHER situations, since I still can't type or hold things, but there you go.
no subject
Date: 2012-12-21 07:20 am (UTC)ps: HAVE A GOOD CHRISTMAS.
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Date: 2012-12-21 02:18 pm (UTC)If you find yourself nervous about putting paint to fabric, don't be afraid to spend your time laying out what you want. I sloppily cut out samples of my version of the Dick shirt MANY TIMES before finding the exact layout that I wanted. I taped them to the shirt and put on the shirt to get an idea of exactly where the design would sit on my body and how big each logo would be.
Oh, and on pulling the fabric tight—if you want it to look more screen printed (which is my preference), stretch it just a little to get more paint in the design area without distorting the final result.
I LOVE MAKING STUPID SHIRTS!
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Date: 2012-12-22 04:21 am (UTC)no subject
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