Clean the floor thoroughly with soap and water and let dry. By cleaning the grout, you ensure that the sealant will adhere efficiently and completely to the floor.
Wet a sponge and apply the sealer to the sponge. Rub the sealer onto the bathroom floor. Make sure you cover the bathroom floor as completely as possible. Let it dry for an hour.
Apply a second coat of sealer to the floor.
Wipe any excess sealer from the bathroom floor with a rag. Let the floor dry for at least eight hours before stepping on it.
Seal around the base of the walls as well as the shower and tub with caulk.