Brian, we sanded all the gellcoat that we were painting down with 150grit paper and a palm sander. Then put the awlgrip epoxy primer everywhere, then we painted the awlgrip on top of the primer. You have to put it on in thin coats because it will bubble where you are too thick, we just sanded with 220 to get a few runs out in spots on the first coat then I decided to only reduce it about 10% instead of the package instructions and it tacked out quicker and had less runs. You can work the paint for about an hour with a china brisle but you just push it around like rubber until you get any runs, bugs, leaves, or whatever out.