Painting Resin.

So I was going to pigment a resin cast, then go back and paint details in (to bring out the carved scales)  but, how should I prep the resin base for painting? What sort of primer? and can primer be thinned/ sprayed though an airbrush for an even, solid coat?

Thanks!


Dragon mask WIP, if curious; Scales and so forth need to be added and refined.