The most effective way to get rid of rust stains is to use a professional rust remover (available at most major super-markets and janitorial supply houses) and follow the manufacturer's instructions. A home remedy would entail rubbing the stain with salt, then pouring a few drops of lemon juice on top. Let the garment dry in the sun. Repeat as necessary. Note: Chlorine bleach will set a rust stain. If your household water supply contains rust, discontinue use of chlorine bleach.