Wash your garments as you normally would, using your preferred laundry detergent. In some cases, this alone may remove the mildew.
Mix salt and lemon juice into a paste, and spread it over mildew stains, or simply sprinkle lemon juice directly onto the stain, and pour salt on top.
Hang the garment in the sun for several hours. Do not bring the garment back into your home until it has dried completely. Wash the garment as you normally do.
Pour 2 cups of sodium borate and 2 quarts of hot water into a bucket. Sodium borate, sold commercially as borax, can destroy mold and clean stains without harming fabrics. Be sure to use hot water, because borax crystals require hot water for activation.
Allow the fabric to soak for several hours in the borax solution until all mildew stains disappear.
Remove the garment from the borax solution, and hang it in the sun to dry. Do not bring it inside until the fabric dries completely. Launder the item as you normally do.