Staying hydrated during the summer heat waves is not only important for safety reasons, it's going to automatically make you feel cooler. Drinking water regularly will keep your body cool and help you stay comfortable for hours after you chug-a-lug. During the summer try to drink at least eight ounces of water every hour to stay cool.
Grab a cold one
...a cold towel that is. There are specialised towels that have a cooling effect--when you place them on your skin it instantly cools you down. These towels are thin and are often sold in sporting goods stores--all you have to do is dampen the towel, snap them in the air and drape them on the back of your neck. If you don't want to spend the money, make one yourself by dipping a thin wash cloth in some cool water, ringing it out and draping it on the back of your neck. You could do the same thing with a damp paper towel.
Take advantage of the night air
Because air is cooler at night, you may not need to crank your air conditioner. Instead, open up a few windows in your bedroom and let the cool night air in. If you have a ceiling fan in your room, be sure to turn it on to keep the air circulating. You could even utilise a window fan to suck the remaining warm air out of the room by facing it out or setting it to "exhaust".
Keep your blinds closed
Your window blinds and shades are your biggest ally in the fight against summer heat. In the summer they keep the sun out and in the winter they
keep the heat in. Before you leave for the day, be sure to close your blinds and/or curtains so that the sun's rays aren't beating down into your living room for 10 hours. Thermal-lined curtains can help keeping the heat out in an instance like this, so it may be time to invest in a pair.
Adjust your sleeping arrangements
Trying to sleep in the summer is tough when it's too hot to get comfortable. If your bedroom is generally the warmest room in the house, try sleeping in another room if possible. Remember, heat rises so if your bedroom is on the second floor and your guest room is on the first, maybe it's time to test out that guest room mattress for a few nights.
If you don't want to relocate your entire life because of the heat, try storing your blankets or sheets in a cooler room within your home. When you get up in the morning, grab your blanket and sheet and hang them up in a cooler room. Right before you head to bed for the night, put them back on and you'll soon find some instant relief. Of course, the simplest solution is to sleep sans-blanket.