Compass Navigation

Diver demonstrating underwater compass navigation

Chris A. Crumley/Alamy

1) Line it up. Point the long line on your compass — the lubber line — in the direction you want to swim, and make sure your body is pointed in the same direction.

2) Take a heading. Rotate the bezel — the spinning wheel on top of the compass — until the two hatch marks sit over the tip of the north arrow. As you swim, watch to make sure the north arrow stays between those marks.

3) Proper positioning. Hold the compass flat and in line with your body at all times. If you get off-course, turn your whole body, not just the compass, until your heading is back on track.

4) Avoid tunnel vision. Look up and around periodically to keep an eye on your surroundings. If there is a current or heavy surge, you can be pushed off-course, even if your heading stays true.

5) Happy returns. To return to your starting point, turn your body until the north arrow points at the single hatch mark on the opposite side of the bezel and follow steps one through four on the reciprocal heading home.