Stand in the water at mid thigh depth and walk. Start slowly and try to make as little a wave as you can. If you have a partner have him close his eyes and sense your arrival. This is a good way to learn to walk softly. Next walk or try to run as fast as you can a few times. After you do this think for a while and try to start the movement from the body were the breath is and run a few more times. With a partner exchange a few leg hits underwater and than above the water and note how you adjust to it.
Lift both legs in the water and make a line with your body parallel to the ground. change the tension and light angles in your body to be able to breath from time to time and remain calm and relaxed as much as you can. (unless you are in the dead sea in which case just relax :))
Fill your mouth with water and breath as much as you can through the nose. Do a few push ups and squats and than a few sit ups and leg raises and note how this effects your movement and breathing. Being able to work with an uncommon situation is a sign of good improvisation and awareness skills.
Have fun.