Using a soft rubber grout float apply the material with diagonal sweeping movements to the grout joints, taking care to fully compress the grout into the full depth of the joints. Work in manageable areas, and clean off any residues when the grout has begun to firm up in the joints but not before it sets on the tile face. Cleaning with a damp and not overly wet clean foam rubber sponge will provide best results. Changing the cleaning water as it becomes contaminated with grout residues will also aid cleaning. When the grout has set, any remaining grout film can be polished off the surface with a clean damp cloth.
N.B. Do not over wet the grout as this will result in a weakened grout joint and can also cause efflorescence, a white soluble salt, to form on the surface of the finished grout joint.