Keep your blinds closed
As simple as this tip may seem, it is notated that up to 30% of unwanted heat comes from your windows.  Utilizing window coverings can save you up to 7% on bills and lower indoor temperatures by up to 20 degrees.  In other words, closing the blinds essentially prevents your home from becoming a miniature greenhouse, which is especially true with south and west facing windows.

Better yet, invest in blackout curtains
Blackout curtains block sunlight, naturally insulating the room in which they are installed.  Consumer Reports recommends neutral-colored curtains with white plastic backing to reduce heat gain by up to 33%

Be smart about your doors
Closing off unused rooms will prevent cool air from permeating these areas during the hottest part of the day.  When the nights are cooler you should capitalize on the cooler weather by letting air flow naturally though your home.

Hack a fan instead of turning on the A/C
Even the best air conditioner can’t give off a faux sea breeze, however, this simple trick can.  Fill a mixing bowl with ice, (or something equally cold, like an ice pack), and position at an angle in front of a large fan so the air whips off the ice in a extra-chilled extra misty state.  Ahhhh!

Swap your sheets
Not only does switching your bedding seasonally freshen up a room, it also is a great way to keep cool.  While fabrics like flannel sheets and fleece blankets are fantastic for insulation, cotton is a smarter move this time of year as it breathes easier and stays cooler.  As an added bonus, get a buckwheat pillow or two.  Because buckwheat hulls have naturally occurring air space between them, they won’t hold on to your body heat like a conventional pillow even the packed together in a pillow case.

Set your ceiling fans to rotate counter clockwise
You may not realize that your ceiling fan needs to be adjusted seasonally.  Set your fan to run counter clockwise in the summer, at the higher speed, the fans airflow will create a wind chill breeze effect that will make you and your guest feel cooler!

Ditch the incandescent lights
If you ever needed motivation to make the switch to CFLs, (or compact fluorescent lamps), this is it.  Incandescent bulbs waste about 90% of their energy in the heat they emit, so tossing them to the curb will make a small difference in cooling your home while lowering your electric bill.