For cooler summer sleeping, prepare during the day by avoiding heat buildup in your house.
Close the blinds or curtains to block the sun and close the windows if the temperature outside is higher than inside. As the sun begins to go down and the air outside cools, open the windows, let a cross breeze through the bedroom, and keep your windows open while you sleep. Since heat rises, sleep in the bedroom on the lowest level.
Many people find fans helpful during the summer. Use a ceiling fan if you have one, or place a portable fan near an open window, leave the bedroom door open, and open other windows in the house to allow air to move. If you have a fan that fits in the window itself, another trick is to direct the fan to blow warm air out of the house. To do this, put a fan in the window facing out and make sure there are no big gaps around the edges. Close all the windows and doors through which air can enter, except the one nearest the bed—that way a stream of cooler air is pulled in one window and warm air is blown out another.
Dress in light breathable cotton pajamas. If you sweat a lot at night, consider keeping an extra set by the side of the bed for a quick change. Take a shower before going to bed. If it works for you, keep a spray bottle, cool facecloth, icepack and a glass of ice water by the bed as well.