Kevin Vang writes:

Way back when I was a 15 year old poolrat, one thing we all had
to do to pass the Red Cross Lifesaving Course was to jump into
the pool fully clothed, then strip down in the water and turn
your pants into a PFD by tying knots in the legs and blowing them
up. It wasn't hard to do back then, but I may have been slightly
more limber then than I am now.

Of course, if you are in water cold enough to make you wear
waders, I think the extra insulation they would provide would
be more useful than extra flotation. I believe the definition
of a PFD is "a device to prevent you from drowning long enough
to die of hypothermia."

Kevin

That was standard training in Navy bootcamp back in the mid 50s. You had to
use your trousers, jumper, and even your dixie cup white hat. The trousers and
jumper could support your weight fairly well. You could trap air in the hat,
but I wouldn't want to depend on it for very long.