method, you'll need pastel dye sticks (we recommend Pentel Fabricfun brand), which can be purchased at most fabric stores. You can draw directly on fabric with them, but since the color isn't permanent until it's pressed with an iron, you can also erase most mistakes with soapy water.
Stretch and pin a cotton jersey to a piece of cardboard. With a ruler and chalk, draw a single line across the fabric wherever your child would like to create a stripe. Apply strips of masking tape 1/4 to 3/4 of an inch above and below the chalk line (depending on how wide you want the stripe to be). Use a dye stick to color between the tape strips, using even strokes in one direction only. When all of the stripes are completely filled in, wipe away stray dye flakes with a damp cloth. Then carefully peel off the tape. Lay white paper over the colored area and press with an iron on a cotton setting (a parent's job). Try not to move the iron or the dye may smear. When the dye is visible through the paper, the stripes are set and will no longer wash out.
