First CLEAN IT, use a rag with some lacquer thinner and lightly clean it, then spackle any dents, cracks or holes using spackle, then caulk the edges where necessary [where it meets the wall or adjoining surface(s)]… then prime it with an oil base primer… let it dry, then finish coat with a semi or gloss paint (acrylic), color of choice, use HIGH QUALITY PAINT (and tools)…