Here are some tips to keep you afloat until help arrives:

Leave your clothes on, but take off heavy shoes or anything in your pockets that might weigh you down.

Float on your back as much as possible. Kick only when you have to.

Signal for help while treading water. But try to conserve energy by moving your arms and legs as little as possible.

In cold water, moving around too much saps your body temperature, meaning hypothermia can set in faster.

If tossed a line, wrap it around your chest and tie in a bowline knot.

If a rescue boat arrives, stay away from both the stern and bow.