Fill a bucket with 1 gallon of warm water and add ½ cup of liquid detergent. Dip the brush into the mixture and scrub the terrazzo shower pan until it is clean. Rinse the pan with water.
Clean the shower pan more thoroughly with a powdered bleach or 100-grit aluminum oxide paper to remove any stuck-on stains. Spray bleach on the floor and let it sit overnight to remove penetrating stains on the terrazzo shower pan. Rinse well in the morning.
Allow the shower pan to dry completely.
Add a coat of the terrazzo sealer over the shower pan. Wipe the sealer into the floor with the cloth until completely covered. Allow the sealer to dry completely before use.