Most of the times you will need to heat set your paints so that they can be washed without fading or bleeding. There are a few ways that you can heat set your airbrush art onto the t-shirts so that it lasts. One way is allow the design to fully dry then place a cloth over it and iron the shirt with the cloth between the t-shirt and the iron. Always keep the iron moving though so that you do not burn the material. Another great way if you are doing this at home is to allow the design to dry then turn the shirt inside out and throw it into the dryer for about 40 to 45 minutes on the highest heat setting. After this your design will hold up when laundering.
If you use a paint that does not require heat setting then you should still set the design. A great way to do this with paints that do not require heat setting is to place the t-shirt by itself into a sink full of cold water that has salt mixed into it. The cold water and salt will help to keep the shirt when it is laundered from fading or bleeding.
Placing airbrush art onto t-shirts can be fun and exciting. But you are not limited to t-shirts. Get creative and airbrush designs onto cotton underwear for you significant other. Airbrush socks for your family. The possibilities with clothing and airbrush art are limitless.