A Guide to Stain Removal. Stains need all the help they can get. Salt is there to lend a hand.
Blood: Soak a blood stain on cotton, linen, or other natural fiber in cold saltwater for 1 hour. Wash using warm water and laundry soap, then boil the fabric in a large kettle of boiling water. Wash again.
A fresh blood stain should disappear easily if it is immediately covered with salt and blotted with cold water. Keep adding fresh water and blotting until the stain is gone.
Gravy: Try covering a fresh gravy stain with salt and letting it absorb as much of the grease as possible. A stubborn stain may need a 50/50 solution of ammonia and vinegar dabbed on and blotted until the stain disappears.
Grease: Remove a fresh grease spot on the fabric by covering it with salt. Wait for the salt to absorb the grease, then gently brush the salt away. Repeat until the spot is gone, then launder as usual.
Double-knit fabrics can be a stain challenge when it comes to grease. Add 1/2 teaspoon salt to a small dish of ammonia, and dab the mixture directly onto the grease spot. Let sit, then wash as usual.