Monty's right. There is no certain color or combination that is best because we all see color differently.

CONTRAST is the key

I like to use at least 3 colors - usually a white background with 2 darker contrasting colors. Red, White and Blue is a favorite scheme of mine (There's nothing like red wingtips on a white background to be able to see a plane for miles!)

And keep a good difference between top and bottom! I usually like a darker underside.