I'm doing a cake with a 3D checkered flag (car racing) this weekend. I am thinking of doing it out of 50/50 in white and then somehow painting the black squares...any thoughts on the best method to do that? Any pictures of similar things?

Two ways; roll all white and apply black squares(if you want a flag with movement print one, and use it as a template.) 2nd, white back ground, let it dry or partially, tape it off with blue painters tape, then airbrush in the black.