I am continuing work on my first real costume effort and need advice. What is the best way to paint a latex Cap helmet? I am looking for both method and type of paint. Any help is appreciated. Thanks!
You can brush them on, or airbrush them on.... I always recommend using the airbrush, unless you are really really good with the bristle brush and can minimize the brush strokes from showing up.
If those paints are not what you had in mind, then my next suggestion would be to custom mix your own paint using a 50/35/15 : naphtha/rubber cement/pigment mixture, as explained in this tutorial I made a while ago...
You can also use pigments in the casting process. Try finding something designed for latex specifically. I know a lot of people tint by mixing in acrylic paint; this works, but over time the latex reacts with the acrylic and breaks down sooner. I use Berman Skinflex Pigments. As to overpainting, Studiocreation's got the right idea for sure.