- 1). Take the object outdoors and wipe away any surface mildew using a dry cloth or brush. Put on a pair of rubber gloves for protection and wipe the dry traces into a trash can. If cleaning in a windy environment, you may also want to wear safety goggles.
- 2). Leave the object in the sun to dry if active mildew remains. If the stain appears moist, accompanied by a musty odor, the mildew is active. By leaving the object in direct sunlight until it dries completely, you effectively kill the active spores.
- 3). Apply an appropriate liquid solution using a soft cloth. If the stain appears on clothing or other fabric, dab it with lemon juice and sprinkle salt to create a powerful combination of sodium chloride and citrus acid. If the stain appears on wood, dab it with oxalic acid, often marketed commercially as wood brightener. If the stain appears on a paper surface, dab it with bleach.
- 4). Rinse the surface of your object by scrubbing it with a soft cloth or sponge soaked in clean water. When rinsing the bleach from a paper surface, use only a damp cloth and dab the object carefully to avoid ruining the paper.
- 5). Place the object in direct sunlight for several hours to dry. Dry it completely before restoring it to its original location to ensure no mildew spores remain.
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