In real life, pilots plan their trips very carefully to make sure they have enough fuel for the journey, but sometimes they need to travel farther than they can get on a single tank of gas. Microsoft's Flight Simulator X allows you to recreate that same level of realism, permitting you to land at an intermediate airport, refuel and then take off to complete the rest of your journey.
Taxi off the runway, keeping your engine power low and turning by using your rudder, and not your ailerons, which won't turn your steering wheel. Locate the parking area, a large concrete area adjacent to the airport's gate if it has one.
Park your airplane in a fuel station which is located next to clearly marked fuel trucks. Check to make sure you that you're parking in a spot that's appropriate for your aircraft's size. The airport won't refuel you if you park in a spot intended for a much larger or smaller airplane. Come to a complete stop, and turn off your engine by pressing "Control," "Shift" and "F1" simultaneously.
Press "Shift" and the "F" key at the same time to summon the refueling truck; the rest of the refueling process will be handled by the airport. After you are completely refueled, perform your normal aircraft start up and takeoff procedures, and continue with the rest of your flight.
If you accidentally land at an airport without a refueling station, you can manually increase your fuel supply by clicking "Aircraft" at the top of the screen, selecting "Fuel and Payload" to enter the payload menu. You can then click "Change Fuel" to refill your tanks.