Find out how many miles you can get on one tank of gas. Fill your gas tank to full, and reset your car's trip odometer. Drive your car until the "Gasoline" light turns on, or until you are almost at "E" if your car does not have a gasoline alert light. Look at the odometer and write down the number of miles you traveled.
Use a GPS or online map website to plot out your road trip. Mark down which cities you plan on stopping in to fill your car's tank. Pay attention to how many miles it takes to get to each city; don't plan on stopping at a city that is 50 miles further than you can travel on one tank of gas. Most GPS devices and online map websites will show you how many miles it takes to get to a certain point on the map.
Use an online gas finder to find the cheapest gas stations at the cities you plan to stop at. Online gas finders, such as MSN Auto's local gas prices, GasBuddy's national gas station locator and MapQuest's gas prices locator will give you the prices and stations for your desired city. Bring along a laptop or cell phone with Internet capabilities to view updated gas prices, because the prices you see when you embark on your road trip may be different than when you stop at the first city to get gas.
