A cold shower doesn't just temporarily cool you down. "It lowers your skin temperature and can actually reregulate how much you sweat," says Loretta Ciraldo, MD, voluntary professor of dermatology at the University of Miami Miller School of Medicine. Post-shower, towel off and sprinkle powder (like Zeasorb Super Absorbent Powder) over areas that tend to be particularly sweaty. If your feet get slippery in summer, use the cool setting on your hair dryer to dry them completely, then pat powder on them (don't miss between your toes). And consider upping your antiperspirant power. Secret Clinical Strength and Degree Clinical Protection contain the highest over-the-counter concentrations of an effective sweat-duct-blocking ingredient (aluminum zirconium tetrachlorohydrex glycine, FYI). For the best results, apply antiperspirant to totally dry skin before bed. If you need even-more-potent sweat prevention, ask your dermatologist for a prescription antiperspirant, like Xerac AC or Drysol. And if you're a bucket sweater, there's always Botox. Underarm injections can cost up to $3,000, but you'll stay dry for at least three—and up to seven—months.