To paint old bathroom cabinets, begin by cleaning and sanding them to remove any old finish and ensure good paint adhesion. Apply a primer to the cabinets to prevent bleed-through and enhance paint coverage. Once the primer is dry, apply your chosen paint in thin, even layers. Finish with a protective topcoat to increase durability. Allow ample drying time between coats.

Clean, sand, prime, paint in layers, and apply a protective topcoat.