Well, the straight answer is - nothing. This year we had about 3 days of real heat, and we are in Central Italy, in July!
But I have accumulated years of experience, having lived in Rome too, so here's what I do:
- Always have water with me. Always!
- Avoid eating heavy, greasy foods. They don't settle well with me during summer. I usually have something that doesn't require much cooking, mostly in the form of salads. Pasta, or rice, or meat, or fish salads. I should do a summer salad series on my cooking blog, whenever I remember to take pictures of my dinners...
- Eat lots of beautiful summer fruits! They'll show their goodness on your skin too!
- Wear light pretty dresses and skirts! (I am lucky I can wear tank tops even at work, since I have to wear a lab coat and nobody is seeing my clothes...)
- Ice cream!
- When it's really hot I put my feet in a bowl full of water and ice cubes. It's really refreshing.
- And I use some refreshing gel on my legs.
- As soon as I can, I go to the beach! Never in the hot hours though. And I spend a lot of time in the water if it's really hot.
- My drink of choice, besides water, is cold white wine.