From Moneysavingtips.org follow these few steps that can help you make the gas in your tank take you a bit farther.
1. Steady driving saves gas. Avoid jack-rabbit starts and sudden stops. Let your car slow down by taking your foot off the gas. It takes more gas to go faster, so go slower when you can.
2. At long stops such as waiting for a train or in the credit union drive-though, turn the engine off if you can. At stop lights you can put your car in neutral which will reduce the amount of gas it is using while idling.