GPS, Map, Compass. . . there's more than one way to use that combo. If the GPS is functioning and you mark waypoints on the way in/up, you just select the relevant waypoint, get a bearing and walk to it. Watch your step, don't walk off a cliff. If there is a bridge across a stream or a major fork in the trail, mark them as WPs. After you use it enough you'll know what to mark and after that you can fly IFR -- trust your instruments.