Gas prices tend to go up in summer because of increased demand.  Combining errands saves both gas money and time.  Find the cheapest gas along your normal driving route.  Try to choose regular gasoline, not premium, unless your car's manual recommends a higher-octane fuel.  Driving defensively, following speed limits and avoiding aggressive stops and starts also saves gas.  Look for opportunities to take a walk, bike ride, or public transit or enjoy carpooling with friends.  And  Finally, try to avoid driving in rush hour as much as you can.  All that time idling in traffic wastes a lot of gas.  Perhaps you can adjust your work schedule so you can avoid traffic.  Maybe you can even telecommute occasionally.
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