Use lower octane gasoline for your car. If you use high octane fuel it is waste of money. If you're confused as to which grade of fuel works best for your car, open up your owner's manual and take a look. When filling your car's gas tank, don't top it off. See to it that you tighten up your gas cap each time you fuel up your car. Try parking your car in the shade of a tree whenever possible. Buy a good windshield shade as it blocks sunlight and helps to keep heat out of the inside of your car. Park your car in the garage as it will keep your car warm in the winter and cool in summer. Don't drive your car in under inflated tires. Under inflated tires wear down more quickly and then also lower your car's gas mileage. If you use manufacturer's recommended grade of motor oil, you can improve on your car's gas mileage by 1 percent to 2 percent. Give your car engine regular tune-ups. Don't skimp on maintenance.