Please read this first and see if you like it before visualising it, as it can be a bit confronting to start.
You imagine yourself in the water. It feels heavy with lots of pressure on you.
You can't breathe properly. You can't even move.Your body is full of water.
You can now feel that the water is going down slowly through your arms towards your finders and out.
The water does the same thing through your chest, stomach, legs and toes, and through your neck up towards your head and through your ears.
Each time you feel lighter and lighter and you can breathe much better. You can now feel the fresh air and energy in your body.
Your mind is clear and you can remember everything.