After you've established neutral buoyancy, your instructor will have you swim 10 meters/yards or farther, remaining neutrally buoyant. During this swim, pretend you're swimming over a reef with sensitive aquatic organisms and avoid any contact with the bottom. This simulates how you swim avoiding damage to the environment when making open water dives.

Cramp Removal
A cramp is a painful, involuntary muscle contraction, which, as a diver, you may experience in your leg or foot muscles. Several things can contribute to cramps: dehydration, working the muscle beyond its fitness level, restricted circulation, cold water, and all of these working together. Your fins can contribute to cramping if the blade is too large for your leg strength, or if the foot pockets are too small and your feet don't go in them properly. Fitness, proper fin selection, practice, proper insulation and pacing your activity, will help you avoid cramps.

But they can happen anyway. Like most problems, it's more of an irritation than an emergency if you stop and think about what to do. For a cramp, stop and rest the cramped muscle. Stretch and gently massage it to increase circulation and pull out the cramp. If you have a leg cramp in your calf muscle, you can stretch it by grasping the fin tip and pulling it toward you while you push with your leg. Your buddy can also brace the fin tip for you