My son had wacky hair day at his school recently, and as his hair is always kept short so, naturally, I was at a loss for what to do with his hair. But then, a friend of mine gave me this little tip: mix shampoo with finger paint! Not only did it work but it washed out like a dream without any extra scrubbing! No residual colour was left behind, and I had painted in seven different colours into his ash blond hair. Dab a fair amount of shampoo onto a Q-tip, dip it into the paint, and then simply paint the hair :) it dries like hair gel, so you can style it once it's painted.