Yeah, the proper way to do it on new parts is a light sand with finishing grade sand paper, then a good prime coat, then apply the base coat, then apply the clear coat. It depends on what you're painting as to the type of primer you should use. Some plastics and urethanes require a special ABS primer, so you may want to check to be sure that you don't need that. Also different color paints require different color primers to really make the paint "pop" after the base coat is layed down. There lots of little tricks....I'm not a profesional painter by any stretch but I can usually make out ok. Lately I've been kind of experminting with doing flame jobs and scallops.