This exercise involves inflating clothing with air to stay afloat. If you do not have a life jacket when in the water in an emergency situation you can make your own emergency water flotation device using your clothing. Lifeguards and Boy Scouts practice this technique by removing clothing such as pants or shirts while underwater. This is a useful skill to learn and great fun to practice.
This may not work with all clothes.
You may have to experiment a bit with different outfits.
Waterproof or cotton clothing will work well for this purpose.
Rainwear or canoeing cags are probably best.
Other clothing might work, but air may leak faster.
It must be free of holes.
To retain air, cotton material that is above water must be kept wet or it lets air through.
Make a close seal with the collar around your head. The nose stays out above the collar, the mouth is just inside.
Now breathe in with the nose and exhale with the mouth into your anorak or T-shirt. Exhale below the collar.
Notice how the air volume builds up over time. If you keep a good collar seal the air with stay in for a good while.
A tight collar is an advantage.
Long sleeves hold more air.
The amount of air that cotton trousers will retain in water is enough to keep you afloat if you remain calm. When the ends of the legs or drawstrings are tightly tied, each leg will hold a pocket of air.
Remove your trousers while swimming in deep water. Tie knots into the lower legs or tie the trouser legs together, and button or zip up the fly. By tying a knot in the legs of your trousers you can raise them above the water to fill them with air which enables them to float.
Inflate your trousers with one of the methods below. Float with this buoyancy aid for 1 minute. Re-inflate as required. Swim 15 meters using the inflated trousers for support, then show how to re-inflate them while using them for support.
Blow air into your trousers
Put your mouth inside the collar but keep your nose out. Now inhale with the nose, then exhale through the mouth into your trousers. Soon they fill with enough air to keep you afloat.
Hold the waistband open underwater with one hand. While using the scissor or frog kick to stay afloat, splash water and air toward the waistband opening with a downward motion of the hand. Stop the stroke at the opening. Forcing a current of water and air bubbles into the trousers straightens the pant legs. The water passes through leaving air trapped at the ends. Gather and hold the waistband together. Slip your head between the trouser legs, and place the knot behind your neck. Lie back and float.
Hold the waistband open with both hands behind your head. Then sling the trousers over your head, scooping in the air that is trapped when the open end of the trousers (the waistband) hits the water. Now position yourself between the legs and stay afloat.