After you have reviewed the appropriate material, installed and set up your flight simulator and pilot client, and planned your route, you will want to file a flight plan with VATSIM. This will allow the controllers to see your planned route and issue a clearance for your flight. Remember, even if no ATC is present when you begin your flight they may come online at any time, therefore having a flight plan is essential to enable the controller to provide ATC services.

You may file your flight plan via the VATSIM flight plan page, but each of the pilot clients includes an option to file your flight plan directly.