Preperation on the hull is a must! If the hull is new? Then use tar wax and grease remover or good dishwashing deturgent on the hull first. If the hull has no defects then watersand it with 400-500 grit wetsand paper and then scuff the rest with a red scotch bright pad... But if it got defects like pin holes dips and deep scratches,Then sand those areas with 180... Then use polly puddy like USC ICING. You can sand it with 180-220 sand paper,then prime and block it twice..Primer wise,you can use Dupi-color or NASON rattle can...or Use 2K primer.. all works great. After your done primming those areas then wetsand it with 400-500 grit paper. Then use tar wax and gease remover again. This will remove oils and other contamations from the boat surfaces....Ok to seal your boat for paint. You can use Dupi-color primer sealer or etch primer... Both helps the paint bite/adhere better to the surfaces and seals any body work from showing up...Then use a tac cloth to whipe off the boat before painting it... By doing this will get any dust off the hull before painting it...On WOODEN HULLS AND WOODEN RIGGERS you do not have to prime them. Just have them sanded good with 400 then paint... Found that out by a close friend of ours thats been building boats for 30 years...Smaller rigger a sentive to weight and primer will add weight to it...Ok we're ready to paint...