Speeding to a stop

Accelerating to a red light is a waste of gas. If an upcoming light turns red, remove your foot from the gas pedal and coast the rest of the way, applying the brake when necessary.

Air/tires

Optimally, you should check the air in your car's tires every time you fill up for gas. However, once a month works just as well and is equally as important- low tire pressure results on more strenuous wear-and-tear on the tires causing them to not last as long. Also, improperly-inflated tires lowers your car's MPG.