Empty the cabinet of all its contents and place them in a safe place.
Remove the shelves from the cabinet, if they are removable. This makes it easier to refinish. If you cannot easily remove the shelves, leave them in.
Scrape all of the contact paper off the shelves with a putty knife. If the paper is difficult to remove, spray it with warm water. After a few minutes, continue scraping. Not all cabinets have contact paper lining. If yours do not, skip this step.
Sand the surfaces of the inside walls, inside back and shelves with 400-grit sandpaper. Graduate to 600-grit, 800-grit and then 1000-grit to restore the smoothness of the wood.
Wipe the surface of the cabinet down with a tack cloth.
Paint the inside of the cabinet with semi-gloss or high-gloss latex paint and a paint roller. Use a paintbrush to reach areas that you cannot reach with the roller. If you painted the outside of the cabinets, use the same type of paint. However, it is up to you if you use a contrasting color. Allow 24 hours drying time.
Place the shelves back into the cabinet, if necessary.