Mix the cornstarch and the water thoroughly, and then add the food coloring. Repeat for each color of paint you would like to have. We made red, blue, yellow and green.
I found that foam brushes worked well, but I am sure you could use whatever you have in your craft cupboard/drawer.
We had a great time with this simple summer activity, and we can't wait to make another batch of this easy and inexpensive sidewalk paint! Let me know if you give it a try.
Gina Bell (aka East Coast Mommy)