Here is what a vehicle driver can do in a single round:
Optional Attack Action: If the driver wants, he or she can use his or her attack action before moving the vehicle. If the driver does so, however, he or she will be limited to a single stunt during movement.
Movement: Move the vehicle any number of squares within the vehicle’s speed category. Along the way, perform any number of simple maneuvers (limited only by their movement cost). The driver may also attempt a single stunt as part of the movement (or two, if the driver didn’t take his or her attack action before moving).