White cotton shirts
Acryllic Paint (I used Waverly Inspirations Chalk Paint in Ocean, Peacock and Pool)
Plastic spray bottles (one for each color)
Package of rubber bands (office supply section)
Plastic gloves (acryllic will come off your hands, but the scrubbing is a pain)
I started with damp shirts and instead of rolling them the way described in the tutorial, I wadded them up into a ball.
This, my friends, is the wrong way. I had to repeat the painting process more than once because I didn't roll the shirt, but wadded it up into a ball.
Next, combine the paint with some water in the spray bottle. I used about 70/30 water to paint ratio, but you have to try for yourself. Too much paint will result in a stiff mess. Now spray. We alternated these complimentary colors for the best effect.
After spaying them thoroughly, I put each shirt into a plastic shopping bag and squished them to get the paint distributed. It didn't work as well as I wanted, because as I said, I wadded up the shirts the wrong way to start. After removing the rubber bands and seeing big blank white spaces, I realized my mistake and had to roll the shirt up again for another round of spraying.
Once you get the desired amount of paint on the shirts, you need to let them dry completely before wearing (or you will wear the paint). I also wanted to make sure my shirts didn't accidentally run in the laundry, so before I washed them, I soaked them in cold water and vinegar for an hour. (It's probably not necessary, but it's the best way to set dye of any kind.)
I made shirts for all of the cousins, but here's the one that turned out best from my grand-nephew.