Don't cross the grain If its wet, its working If it's drying out, apply more Toothbrushes are not power tools Don't use a scraper Don't grind hard paint Corners need longer and repeat applications Don't labour on a reluctant piece Don't change the system Dry wet bits off masking tape before it soaks through Never use ordinary masking tape Don't spray in windy conditions The thicker the old finish, the slower it will be.