If you've noticed ugly yellow spots under the arms of your favorite shirt, don't sweat it. Perspiration stains on cotton tops are the result of a nasty combination of bacteria and aluminum-based ingredients in your antiperspirant. Thankfully, cotton is easier to clean yourself than silk or wool, which are often dry clean only. To erase the stains, target them ASAP, because the longer sweat sits on any fabric, the harder it is to remove.

Step 1

Apply an enzyme-based stain remover or detergent to the stain. Scrub with an old toothbrush to work the product into the stain and help break it up.

Step 2

Mix equal parts water and white vinegar and douse old sweat marks or stains that don't respond to detergent. The acetic acid can help treat discolored areas, especially in white fabrics.

Step 3

Pretreat sweat marks with a paste of equal parts baking soda and water. Let the mixture sit on set-in sweat stains for up to two hours, then wash as usual.

Step 4

Dilute two parts hydrogen peroxide with one part water or dishwashing liquid, then rub it on the stain. When applied to the stain, hydrogen peroxide breaks down into water and oxygen and helps break up the stain in the process.

Step 5

Mix equal parts lemon juice and water and dab it on the stain. Lemon juice is a natural bleaching agent. Scrub the stain gently, then wash in cool water.

Step 6

Mix two crushed aspirin in a half cup of water. Pour the mixture onto the stain and let it soak for two to three hours. Wash to remove the stain and aspirin residue.

Step 7

Mix 1/4 cup of salt in a quart of warm water. Apply the solution to the stain with a washcloth or sponge. Wash in cool water.

Step 8

Sprinkle a little meat tenderizer on dampened stains. Use enough tenderizer to cover the stain completely, then wash in cool water.