The answer to 'grout cleaning tips' is to use a grout brush, grout cleaner, and some elbow grease. First, sweep or vacuum the grout lines to remove any loose dirt or debris. Then, mix a mild grout cleaner with water according to the product instructions. Use the grout brush to scrub the cleaner into the grout lines, working in small sections. Let the cleaner sit for 5-10 minutes before rinsing thoroughly with clean water. For tougher stains, you may need to let the cleaner sit for longer or use a more abrasive cleaner, but be careful not to damage the grout. Repeat this process until the grout is clean.
It's a good idea to clean your grout every 6 months to 1 year to keep it looking its best. If you have extensive grout damage or discoloration, it's best to call in a professional grout cleaning service.