If you aren't careful in the Summer's heat and humidity, especially in the trunk of your car or other dark, damp places, a wet towel will turn mildewy fast! If this happens to you, don't toss the towel. Instead make a rub of 1/4 cup of white vinegar and 1 teaspoon of salt. Rub into any visible mildew spots and wash and dry as usual. The acetic acid in the vinegar will break down the mildew and soften the towel while the abrasive salt will scour away the residue. Result, your towel will look as good as new!