Grout can be applied to the ceramic once the mastic is completely dry. To grout ceramic tiles:
Step 1: Mix the grout to a creamy consistency and set it aside. Wet the tiles so that they do not remove moisture from the grout.
Wear gloves and spread grout evenly over half of the back wall, then use a rubber squeegee to work the grout well into the tile. Wipe the excess away with a wet sponge.
Step 2: Use a blunt stick to force the grout deep into the tile joints. Remove the excess grout with a sponge and continue in the same manner for the remaining area.
Step 3: Allow the grout to dry overnight. Polish off the thin film of grout that has dried on the tile. Run a bead of tub caulk around the 1/8-inch gap between the tub and the first row of tiles. If you have tiled around a window, be sure to caulk it carefully.
Step 4: Apply a grout sealer according to the manufacturer's directions.
Now that you've read the instructions in this article, you're ready to do a bathroom makeover.