As you can see, the surfaced of the red painted buckets were glossy so the first step is to sand it untill you can see a flat surface. First use the 800 grain and then use the 1500 grain to smooth it out. wash the sanded area and dry it between sanding to remove the all the residue from sanding. When the the surface is smooth and no sights of a glossy paint surface, is ready for next step.