"To improve your fuel economy and reduce carbon pollution, go easy on the brakes and gas pedal, avoid hard accelerations, reduce your time spent idling (no more than 30 seconds), and unload unnecessary items in your trunk to reduce weight. If you have a removable roof rack that is not in use, take it off to improve your fuel economy. Use cruise control if you have it, and for vehicles with selectable four-wheel drive, consider operating in two-wheel drive mode when road conditions make it safe to do so.
For more information, take a look at these tips for driving more efficiently. Check out www.fueleconomy.gov, to find the best, most comprehensive information on vehicle emissions and fuel economy." from the EPA website http://blog.epa.gov/blog/2014/04/earth-month-tip-drive-smart/
