On the highway, drive at least 5 miles under the posted speed limit; choosing 55 mph instead of 75 reduces the amount of gas you use by about 25 percent.
Each 5 miles per hour you drive over 60 is like paying an additional $0.30 per gallon of gas, according to the US Department of Energy. Driving at 55 instead of 75 reduces the amount of gas you use by about 25 percent. At the other end of the spectrum, remember that idling gets 0 miles per gallon. Turn off your car if you will be idling for longer than 30 seconds.
OTHER TIPS: Park in drive-through spaces to avoid backing up whenever possible. Remove any extra weight from your car; carrying around 100 unnecessary pounds can reduce your miles per gallon by 2 percent (US Department of Energy).