Sand the entire surface of the furniture that you would like to paint with 120 grit sandpaper. Sanding is important because it scuffs up the surface and gives the paint primer a surface that it will stick to.
Apply a coat of oil-base primer to the entire surface. Oil-base primers are available at hardware stores. Use a brush for smaller areas or a roller for large and flat areas. Allow the primer to dry completely.
Sand the primer with 400 grit sandpaper and apply another coat of primer. Allow the second coat to dry thoroughly.
Apply the finish coat of paint. For the smoothest finish, lightly sand the finish coat with 600 grit sandpaper, then apply another coat.