Use the grout brush or a toothbrush to scrub vigorously at the grout lines, until stains are gone. Rinse with clear water, and sponge up the water. Use a towel to dry the tile completely. Let the tile air-dry overnight before sealing the grout. The scrubbing vigorously is usually why most people call us to come and do it for them. It is exhausting back-breaking work to put elbow grease into those cracks. Why do that when you can just give us a ring and we’ll come out with our state-of-the-art equipment and get the job done for you in a fraction of the time while you sit back and relax! It’ll look better when we’re done too.