If you wash sweaters and delicate items by hand, add 1 or 2 tablespoons vinegar to the last rinse to help remove soap residue, which can be difficult to get out entirely when you hand wash. Silks, however, require a special hand washing treatment. Add 2 tablespoons vinegar to 1/2 cup mild detergent and mix with 2 quarts of cold water. Dip the silk item into the mixture, but do not soak. Rinse well and roll it in a heavy towel to soak up additional moisture. It's important to iron silks while they're still damp.