Mix water with a few drops of dish soap to create a slightly soapy solution.
Dip a clean cloth in the water solution and rub along the bottom of the disc to wipe away light smudges or sticky substances.
Apply a small amount of isopropyl alcohol to the cloth and rub the disc to remove any further debris.
Place a small dab of toothpaste over any small scratches on the surface of the disc to fill them in. Rub the toothpaste in until it is level with the disc, and remove any excess.
Sand the bottom of the disc using a very fine sandpaper. Continue sanding until the entire bottom of this disc is sanded and flat.
Apply polish to a clean cloth, then rub the polish onto the bottom of the disk. Apply over the entire surface until the bottom is shiny.
Apply alcohol to a new cloth and wash the entire bottom of the disc using rubbing alcohol.
Set the disc aside to air dry for several minutes, then test the disc in a player.