Fill a bucket with water and add a small amount mild detergent, such as dish soap or car wash soap.
Soak the sponge in the soapy water and scrub the surface of the umbrella to remove any dirt from the fabric.
Leave the soapy water on the surface of the umbrella for a few minutes.
Hose the soapy water off the canvas umbrella and allow it to dry.
Allow the umbrella to dry thoroughly after it has gotten wet in the rain before you store it inside.
Fold up the umbrella after it has dried and place it in your garage, shed, basement or other storage area. The umbrella should be stored indoors during cold months.
Close the umbrella while it is still outside when not in use, especially if it is windy or a storm is on the way. Tie the umbrella with its ties to make sure it stays closed.
Rinse the umbrella with water when you reopen it to use it. This removes any debris from the umbrella that may have accumulated while it was closed.