Write the next sentence in the following story.

How to refinish bathtubs
Clean the entire surface of the bathtub with chemical cleaners to remove any soap scum and dirt residue.
The chemical cleaners will also help the bonding agent adhere to the surface.
Rinse and dry all surfaces thoroughly.
Use a palm sander to gently roughen the surfaces you plan to refinish to make it easier for the paint to bond with the surface. Tape paper or plastic over any surfaces you do not want to paint.