You can also just go to the hardware store and buy the Krylon H2O paint. It is water based and works great on surfboard foam. Just make sure…as Rich above says…you don’t spray it on to thick or you wont get good lamination when you glass. That rule goes for any paint. Since the rattle can is a little hard to control I keep a clean rag rear by just in case I spay it to heavy so I can just wipe or dab the access off with the rag. All the boards in the pic bellow were done with the H2O spray cans. Here is a link to the paint and the colors they offer-http://www.krylon.com/products/h2o_latex/
Bill