Polyester is a synthetic fiber. It has no natural affinity for perspiration, so you must wear the clothing in which it is used before you are drenched with sweat. The best way to do this is to make sure that your body temperature reaches 100°F or higher when you first put on the polyester shirt/blouse/dress/pants. If there are any other clothes on your person at this time, they will absorb that warmth and prevent the polyester from working its magic against dehydration. At temperatures below 100°F, you cannot expect polyester fibers to pull moisture away from your skin efficiently because they don’t have enough material thickness to hold up under their own weight during perspiration episodes! This means that if you want water-repellent garments such as those made of cotton fabric (polyesters just don’t work well), then remember: You need more than one layer underneath them! Try wearing your favorite tank top over a pair of thin wool socks; then add another pair of thin wool socks over those; and finally wrap yourself in blankets or heavy winter pajamas…and voila: Sweating problems solved!