Allow the adhesive at least 24 hours to set before filling the gaps between the tiles with grout. Grout can be purchased as a pre-mixed paste, or in powder form to be mixed with water. Make sure the powder is mixed to a stiff consistency. Ready-mix grouting is also available in a range of different colours.
Using a liberal amount of grout, spread with a grout spreader, push it well into the joins. Remove excess grout from the tiles surface with a squeegee. Use a clean, flat sponge to wipe away any excess grout before it sets. For wall tiles, use a plastic scrapper along the wall joints to leave a neat finish. When the grout has set, polish the tiles with a soft cloth.