1. pre-washed solid color t-shirt (any color),
2. black permanent marker (medium fine point),
3. acrylic paint,
4. textile medium,
5. cardboard to both create a stencil and use as a guard between the shirt layers, and
6. graphite pencil to trace designs onto the shirt (for dark colored shirts, you will need a white or very light colored pencil).
Step 1: Step 1: Designing the Logo
If this is your first time designing a t-shirt, a logo, or both, begin with a fairly simple design. In the attached pictures, there are two shirts that share a design and one that does not. The owl was based on a logo I had drawn a few years ago and was ideal for testing a logo design because the drawing is fairly simple. On the other other hand, the "Drastic" logo was more complex to work with.
However, both logo styles started with the same process. First, I drew the logos on a regular piece of paper. I cut these out and placed them on fairly thin pieces of cardboard. Cardstock and posterboard also work for this set. Rather than worry about cutting out too much of the stencil, I took a drawing pencil (something like an H-grade pencil) and traced only the contour of the stencil. It was then fairly simple to eyeball the remaining features and draw them directly in without tracing from the stencil.
This method might be harder for some logos, or not ideal for designing the first logo, so you may want to cut the stencil entirely and trace around it on the shirt.
Note: Your pencil lines do not have to be perfect when you begin tracing the stencil onto the t-shirt. They can be erased or you can adjust your design when you begin to paint the logo.
If you find the pencil lines hard to see when you begin applying paint to the logo, go over the lines with a Sharpie. Don't press the marker too hard on the shirt, since the grain of the fabric doesn't always flow with the direction you are moving the marker. Remember that these are just start lines and can be reapplied in later steps.
Step 2: Step 2: Painting the Logo
Solid color t-shirts are fairly easy and cheap to find. If you want an inexpensive t-shirt to test on, you can even search a fabric or craft store, as they usually sell these for around 4 dollars (USD).
I tried this project with two different types of shirts. The first set were regular Jerzees t-shirts. One was grey, the other was red. These held up better than my other choice of shirt - a softer yellow woman's shirt made by Medona. With the softer knit shirt, you have to be careful not to apply coats of paint too thickly because it will make a mess of the shirt after even the first wash. Although not tested as of this writing, the softer knit may still be ideal for this project, but keep that note in mind as you begin to apply the paint.
Fabric paints often come in tacky glittery 3-d textures. But, regular acrylic paint, which come in a much wider array of color choices (including glow in the dark), can be turned into a fabric paint simply by adding Textile Medium (TM). Small 2 oz. tubes of acrylic paint can be found in a fabric or craft store and usually cost less than $1 each. Textile Medium is also sold in 2 oz. tubes (the proportion of TM to acrylic paint is indicated on the bottle). It is a milky white color and thinner than paint and allows the acrylic paint to survive the washing machine.
Note: different colors of paint have different textures; white is typically the thickest. When mixing Textile Medium and acrylic paint (especially if it is not white), you might need to apply a few coats to get a rich color for your logo. This is usually something you get a sense for as you start working with your logos.
The "drastic" logo was done by first drawing the outer contour of the stencil and painting it entirely with the white acrylic and textile medium mixture. When that was done, I added the pinkish coloring for the tube. After the paint dried, I used a Sharpie to add the outlines, fix the lettering, and finally, add the shading.
The owl logos were done a little differently. The initial tracing was laid down in permanent marker and each section of color was filled in separately. When the paint dried, I used a Sharpie to apply the outline again and any shading or extra lines.
Step 3: Step 3: Finishing the Logo.
If you wish to add lines or shading after you have applied your paint, the type of texture you get will depend on how dry the paint is. If dried entirely, the sharpie will go on a little rough because of the varying layer of paint. If the paint is still slightly wet where it will somewhat still show up on your fingertips if you touch the painted surface), then applying the lines with permanent marker at this step will have a semi-geso effect. It will go on smoother and richer. This was done as the final step for the red t-shirt. Whereas, for the first shirt I had done (the yellow shirt), I waited until the paint was dried entirely before adding my lines and shading.
The first two shirts I worked on were the yellow owl logo and the gray "drastic" logo took about two hours each to complete. The red one took much shorter time, but all needed at least a day for the paint to dry entirely. Leave the cardboard inserted between the layers of the shirt until the paint is dry to the touch. This way, they won't stick together and the paint won't bleed through.