While you can use soap and warm water, there are many cleaners available on the market that are designed for use with granite. Apply the cleaner and wipe your counter down. Make sure to use only cleaners or dish soap that is pH neutral, rather than acidic cleaners such as vinegar or ammonia. If you use acidic cleaners, you might remove any sealant from the countertop, which will leave the surface vulnerable to damages. While granite countertops are among the lower maintenance options that you have, it is highly recommended that you keep up on regular cleaning. Regular cleaning can be as simple as using a little dish soap and warm water, so this process is not anything difficult or time consuming. Make sure to use a soft cloth to wipe the surface clean, not a rough sponge. If the granite surface immediately takes in most of the water and develops a dark mark or ring, you need to seal it once every few months. If it takes a few minutes for your stone countertop to soak up all the water, you only need to seal it once every year or two.