Get a few small containers like baby food jars to store the paints. Place one teaspoon cornstarch (or baby powder), half a teaspoon of cold cream and half teaspoon water in each container and mix well until blended. Add a drop of food colouring one at a time until you get the desired colour for each jar.
It’s definitely recommended to start with the primary colours – red, blue and yellow – as you can mix these together later if you need green, purple or orange. But you will also want a jar of white (just leave the mix on its own without food colouring) and black.
I found this on Pinterest.