Go to The State Building located at Post Code 506 and apply for the taxi job. From there you can go to Downtown Cab Co. at Post Code 408 to pick up your taxicab. Using your taxicab, you can provide cab service to other players and charge a reasonable fee for the service. You can also use your F1 work menu to toggle NPC missions. Follow the GPS to the NPC and transport the local NPC players to their destination. Use your F1 work menu to show/hide your taxicab meter and to start and stop your taxicab meter. When you are finished working, return your cab to Downtown Cab Co.