People walking up and down brick steps will track mud, dirt and other debris onto the steps. The easiest way to clean the steps is to rinse them off using a hose as soon as new marks show up on them, or once a week. If you have someone who frequently tracks mud onto the steps, consider placing a plastic doormat at the top and bottom of the stairs.
If there are stains or debris already set into the steps, you should first use a stiff bristled brush to remove any visible dirt or debris. Next, rinse the steps using a water hose with a pressure nozzle attached to it. Mix 1 cup of dishwashing liquid in a bucket with 2 cups of vinegar and 1 gallon of water. Pour this liquid onto all the steps. Be careful, as this will make them slippery. Scrub each step with a soft bristled brush. Rinse the steps off with the pressure nozzle and water hose. Make sure you get all the soap off each step, including in the crevasses, as any soap left can make the steps slippery if it rains. Dry the steps off with a large towel and recheck for stains.
Cleaning with Bleach
If stains are still noticeable on the steps, wet the steps with plain water. Mix 1 part bleach with 10 parts water. Before dousing the steps with the mixture, test a small area near the ground with the mixture. Let it soak on that area overnight. If no less than desirable discoloration is noted, it is safe to use the bleach on the stairs. Pour the mixture on the bricks and let it soak for at least two hours. Then, rinse it off with plain water. However, don't use this mixture as a spot treatment. You must clean the entire set of stairs with this to keep a consistent color.
Light Abrasive Cleaning
Another option for cleaning brick stairs is to use Barkeeper's Friend cleaner, lemon juice and water to clean the bricks. To do this, mix Barkeeper's Friend with lemon juice in a bucket to form a watery paste. Use a soft bristled brush to scrub the mixture onto the steps. Let it soak for thirty minutes before rinsing it with water.