DIY Grout Dying

Clean the floor. Use a high-quality grout cleaner. If possible, purchase the cleaner made or recommended by the manufacturer for your tile or the grout dye you intend to use. If not, use a commercial cleaner that removes calcium, lime, scum and mildew. Follow the manufacturer instructions for application methods and amounts.

Mop the floor clean with hot water twice when you're done to make sure you remove all the cleaning residue.

Place a fan or two in the room to speed up the drying of the floor. An average floor will take four hours to dry. Do not allow any traffic on the floor while it dries.

Shake the grout colorant vigorously.

Pour roughly 1/2 cup of grout dye into a separate container.

Apply the grout dye to the grout. Many grout dyes come with a special brush or tool for the job. A bristle or foam brush roughly the width of the grout will work just as well or better. Dip the brush in the dye and paint the grout with long back-and-forth strokes. Make sure the dye gets into all the pores in the grout. If the grout dye pools, you're using too much. Try not to get too much dye on the tile itself. A minimum of overlap will ensure a good seal and is OK on ceramic tile, but keep a rag handy so you can wipe dye off the tile. Allow the dye to dry for the manufacturer-recommended amount of time. Don't use fans to speed drying time.

Rinse away the excess dye if necessary (Not all manufacturer's recommend this. Be sure to follow the instructions.) Spray distilled water onto the tile and dyed grout, wait two to three minutes and scrub the area clean with a dish scrubbing sponge (not a harsh one used for pots). Rinse the sponge frequently in a bucket of water to keep its cleaning surface clean. Focus your scrubbing action on the tiles. Don't scrub the grout too vigorously or you may lift some of the dye.

Apply one to two more coats to a dry floor if desired following the above instructions. The more coats, the richer and more durable the color.