• Get a map of the area that you are traveling to and study it prior to your trip.
• Use the map and a compass (or GPS) while you are there, and constantly be aware of your position on that map.
• Imagine what the terrain would look like from a bird's-eye view and visualize your place in that terrain. Think of that little "You Are Here" arrow on the big map at the trailhead, and keep it updated in your mind.
• Look behind you frequently, especially if you will be returning in that direction.
• Look for big, unusual landmarks and keep the landmarks in view as much as possible.
• When traveling off the trails, use prominent, distant landmarks and/or a compass to travel in straight lines.
Finally, always make sure somebody responsible knows where you are going, and when you are supposed to becoming back.