1. Turn Your Fans On
Used in tandem with air conditioning, ceiling fans do a fantastic job of keeping you cool by blowing hot air away from your skin. A top-quality ceiling fan with a high energy-efficiency rating may help you slash your air conditioning bill by nearly 15%. Tip: don't bother leaving your fan on when you're out of the room. It doesn't lower the temperature of the air, so you'd be expending energy for nothing.

2. Cover Your South Windows
Do you have south-facing windows in your home? Simply closing your indoor shades and curtains is marginally useful in barring unwanted heat, but for optimal results, you should prevent the sun's rays from touching the windows at all. Install awnings or long overhanging roof shades over all your south-facing windows and watch for a noticeable drop in your next cooling bill.

3. Nurture Your Garden
Get those gardening gloves on and plant a tree—or several. Trees and shrubs help to lower your summertime cooling bill in three ways. They absorb greenhouse gases, provide shade, and move water from the soil to the air through evapotranspiration. Many homeowners plant trees near south-facing windows, but if you live in an area with cold winters, you may want to position your trees where they won't block any sunlight in the cold season.

4. Make the Light Choice
Dark roofs suck in solar heat, raising the temperature inside your home. "Cool roofs" are becoming increasingly popular among eco-conscious—and budget conscious—homeowners. Paint your roof white, or go for a "green roof" with plants growing on it. Either option will make a serious difference to your air conditioning bill.

5. Insulate Your Home
Why pay to cool your home when you can take steps to prevent it from heating up in the first place? From popular fiberglass to eco-friendly denim insulation, there's a world of choice to suit any budget and climate. Although home insulation can carry a hefty initial cost, it's one of the most effective methods of keeping your home cool in summer.