When parking on a hill facing downhill, you should:

When parked facing downhill, turn the front wheels toward the curb. This way, if the vehicle starts to roll, the curb will stop it. Also set the parking brake firmly and place the transmission in 'Park' (automatic) or in first or reverse gear (manual). When parked facing uphill with a curb, turn the wheels away from the curb so the vehicle will roll backward into the curb if it moves. When parked on any grade without a curb, turn the wheels toward the side of the road in both directions, so a rolling vehicle drifts off the road rather than into traffic. This is asked on most state driver tests and is one of the easiest points to lose by getting confused on test day — practice until the rule is automatic.