I've been experimenting with a couple different ways of doing designs and logos on T-shirts (though i imagine most fabric mediums would work for these things). For this Instructable, I wanted to test the Freezer Paper stencil method, which had been described in other Instructables and after this attempt, I found it to be an inexpensive and fairly simple process (altogether, supplies, including the shirt, were less than $12).
You will need the following items:
1) A T-Shirt (or other fabric material of your choice)
It's typically recommended that fabric be washed and dried before applying a stencil, since it tends to shrink in the process. I've never found it to be much of a problem if you don't pre-wash the shirt.
2) Freezer Paper
I have no idea what Freezer Paper was originally made to do -- the back of the box described only craft projects that it could be used for -- but you can find it in the supermarket aisle with the wax paper and foil. It's several feet of paper sold on a large roll, usually for less than $5. **Though I have not yet tested it, you will also find Instructables demonstrating how to create iron-on transfers with Freezer Paper.
3) Acrylic paint
I don't know how well ink might work with a Freezer Paper stencil. The benefits of ink, at least, is that it requires fewer coats. But I've long been in the habit of using acrylic paint mixed with tubes of Textile Medium. You can find both the paint and Textile Medium in small tubes in a craft store. Textile Medium, when mixed with acrylic paint allows it to adhere to the fabric. I prefer this method because, as you may have noticed, paints specifically tailored for fabric projects are often both pricier and also come in a lot of limited, tacky colors and textures as though the only people who would ever want to use fabric paint are six year old girls who love glitter.
4) X-acto Knife
Depending on how complex your design is, cutting the stencil is usually the most time-consuming part of the project. You'll need an X-acto knife or something with similar flexibility for reaching tight areas and later, when removing the stencil, you will need it to pick up any part of the Freezer Paper that sticks to the design.
5) Foam Brush & Palette
Another Instructable describing a similar project cautioned that you should pat down the paint rather than brush it. Part of the reason for this is that you may pick up parts of the stencil by running the bristles of a brush along it. A foam brush is a cheap alternative. They're typically black or yellow squares on a little wooden sticks and they vary in size. The palette, of course, is for placing your paint on.
For most stencil shirts where you are using paint or ink, you need to place a piece of cardboard between the layers of the shirt that are larger than the size of your stencil. It will keep the paint or ink from bleeding through one layer to the other. If you get heavy handed with coats of paint, you may find that part of the cardboard has dried to the shirt. Don't worry, it's just paper. A little water will get it off after everything is done.
You'll need a small amount of tape to hold your design to the Freezer Paper so that the design remains firmly in place as you cut your stencil.
8) Appliances: An Iron and a Hairdryer
The Freezer Paper is eventually what you will be painting on. You will cut your design, then iron it to your shirt, and it should hold until you've completed the painting process. A hair dryer is handy for drying paint much faster than it otherwise would on its own, and that's especially true if you find you need to apply several coats of a color.
9) Medium and/or Fine Point Permanent Marker (Color Should Match Shirt Color)
Let's face it - it's a little boring and stressing to cut out every little hole and crevice, especially if your design includes small lettering. Forget about trying to cut out the wholes in an "A" or a "B," you can always add them in later when the paint dries if you have a medium (and sometimes finer point) permanent marker on hand. Find one that matches your fabric color as closely as possible. I recommend Sharpies because of the variety of colors available.
10) The Design
Well, you're obviously going to need this. How else are we going to make this stencil?
Step 1: Starting With the Design
The first step, obviously, is to think about what kind of logo or design you want to put on the fabric. For this project, I created an image in Photoshop. The pictures I've here are not of great quality, but the shirt says... "Quint's Apricot Brandy... Est. 1974... Amity, MA... Here's to Swimmin' With Bow-legged Women." (Um... it's a Jaws reference).
There's basically two parts to the design to worry about. The first is the text, which was pretty simple. I knew I would be using a dark brown shirt, so I wanted all of the text to be white. The second part of the design is the fruit. I had originally created the design to be easily replicated, and that's why you see each of the fruits colored in a simple 3-color scheme from dark to light.
This could have worked in the final design and is a good idea if you want a stencil that can be quickly and simply applied. When I went to cut the stencil however, I cut the fruit out as one separate part and painted the fruit and shading freehand. In retrospect, I would stick with 3-color scheme design for the fruit.
If you design your image on a computer, you do NOT need to reverse the image when you print it, as you would, for example, with an iron-transfer.