The maintenance of your umbrella will ultimately depend on the specific design of the umbrella and the materials used. The best way to maintain your outdoor umbrella is to follow the brand or manufacturer's instructions. A guide or instructions specific to the design and materials must be included in the package. You should be able to clean your umbrella with water and a mild soap. You can apply this mixture on the umbrella using a soft sponge. It should not damage the fabric. Also, it will dry easily. If powder-coated, you can wipe the umbrella pole with water, but you don't have to clean it often. If you just want to rinse off the dirt, a garden hose can also work. Another way to take care of your umbrella is to store it properly when not in use. This will save you from having to constantly clean your umbrella, and it will always be at its best.