Fan strategically. If the day’s heat is trapped inside your home, try a little ventilation at night or when the temperature drops below 77. A window fan can help; the trick is to face the blades outside to suck warm air out of the house and pull cooler air in. “Kind of surprising,” says Bill Nye, the Science Guy, a scientist, engineer, comedian, author, and inventor. “Having a fan blowing in is a good idea — but it’s not as effective as one that’s blowing out.”

Spritz yourself. Keep a spray bottle in the refrigerator, and when the going gets hot, give yourself a good squirt. “It’s all about thermal regulation,” says John Lehnhardt, an elephant expert at Disney’s Animal Kingdom, in Lake Buena Vista, Florida. “As the water evaporates, it cools you.” While elephants wet their ears first by blasting water from their trunks, humans should begin with their wrists to quickly cool down the blood flowing through their veins.