Don't wet your color coat between color and clear. First, try a blast of air to remove any dust, then wipe with a Tack Rag, or Tack Cloth. Don't use the very tacky ( yellow) ones from the home center, those are for the heavier dust of wood workers. Instead, find an auto-body/paint supplier and get the light blue tack cloths. These have a lower tack, but will absolutely pull away any stray dust particles. Don't rub hard, simply lightly move it over the entire surface with the least amount of pressure you can. If you're not familiar, a "tack rag", as they're often called, is cotton cheese cloth impregnated with a somewhat sticky resin that grabs and holds dust like nothing else, while being chemically inert as far as paint coats are concerned.