"Put on sunscreen. Then do it again," says AAA Travel Counselor Kymberly Schieferstein.
Cotton and silk clothes are both comfortable and breathable. Bonus: "They wash really easily," Schieferstein says. Also consider lightweight, moisture-wicking merino wool, which is great for layering.
Start early, stay late.
Schedule activities in the morning or evening, when the temperature cools. "Last year I visited Myanmar, and I went to see temples early in the day," Schieferstein recounts. "You may have to take off your shoes and walk across pavement."
Care for yourself.
Be sure to stay hydrated and apply sunscreen liberally and often. After a busy morning itinerary, escape the heat with an afternoon nap, or indulge in a spa treatment or other indoor activity.
Savor local treats.
Year-round residents know what foods help keep you cool. Enjoying an afternoon snack also supports the area's economy, and provides opportunities to meet people. "When I was in Italy," Schieferstein says, "I took a lot of gelato breaks."
Take it slow.
Heat and humidity tire the body more quickly. If you can, add extra days to your trip—or at least ease your pace. "Don't stress out trying to cram too much into too little time," Schieferstein advises.