Set up a ladder to reach the top of the awning. Use a broom to sweep dirt, debris and dried mildew spores off the surface.
Put on rubber gloves. Fill a bucket with 1 gallon of hot water. Add two caps full of disinfectant cleaning solution to make a mildew-killing solution.
Wet a clean cloth with the disinfectant cleansing solution. Scrub the surface of the awning to remove mildew stains.
Rinse the awning by wiping it off with a damp cloth. Treat any remaining stains left by mildew with rubbing alcohol. Dampen a clean cloth with rubbing alcohol and wipe the stain.
Wipe the surface of your awning dry with clean cloths. Allow it to air-dry completely.
Protect a canvas awning by spraying it with water-resistant protective spray.