materials that we will need fabric paint (the colors and how many you want), string, alcohol, a container spill water and an old shirt :)
If you want a design like mine, find the middle of the shirt and start to tie tightly with string, a thickness of about two fingers. Tie the whole shirt, much as you want (in my case, I had to tie the front and from behind because my shirt was not cotton, and the ink did not catch so well, but if your cotton is not just a tie time), after doing so dilute some of the ink in a bit of alcohol within the espirrador and start sneezing. Do not worry about blur, it will look good anyway, the more color is nicer. (A cool tip is do not you paint your nails before doing this because they spoil) When you finish painting it, let the shirt dry.
Once dry, untie the knots and can use :D