That will always be my problem - I didn't grow up with that kind of heat. Any other tricks you can share?
One of the best is to take a handkerchief and fold it into a triangle, line ice cubes in the center from about four inches in from each corner. Then roll the ice cubes up in it until you get to the end. Then tie the corners around your neck with the ice cubes in front on your chest. As you play, it will be like air conditioning with the cold water running down your neck. It feels great. When the ice cube melt, just replace them.
If you wear a cap, put an ice cube in it.
Take an extra cooler to the courts with ice and water in it, and just very small towels or wash cloths in it to wipe your face and put on the back of your neck at change overs.
Drink a bottle of gatorade about an hour before your start, and then one while you play, but drink water with it at the same time. You see players do that all the time, pick up two different bottles to drink from, that's what they are doing.
Do every thing you can to get in the shade if there is any, if not use a towel over your head at change overs. Every second out of the sunlight will help.
Hope all this helps. Some of them are kind of a pain in the ass, but the first one is a requirement. I guarantee you, if you do that, you'll outlast anybody out there.