Surface dive into 1.5 metres of water and recover an object with both hands from the bottom. Return to the side of the pool holding the object in both hands. Enter the water from the side of the pool by sliding in from a sitting position. Using any floating object for support, take up and hold the Heat Escape Lessening Posture for five minutes.
Lifejacket or float. Rubber brick or similar that will sink to the bottom of the pool.
H.E.L.P stands for Heat Escape Lessening Posture and it is essentially that. It's a position which can be adopted when you're in a situation where you're essentially stuck in cold water. It prolongs survival time by lessening heat escape from your body and therefore helping to prevent the onset of hypothermia.
It essentially works because key areas in your body lose heat fast than others - groin, armpits, head. By tucking your knees up to your chest and keeping your arms down you minimize the heat which is lost to the water. To use a floating object try either wearing a lifejacket or putting a float between chest and legs.
H.E.L.P. technique can also be performed in a group situation which is essentially just a group hug in the water really. Which has the intent of keeping everyone close to maintain body warmth but the added benefit of making sure you can see everyone else to ensure that everyone is safe. It's more effective in small numbers so that the huddle can be kept small.
Obviously also, the H.E.L.P. technique is fairly hard to pull off without a P.F.D./lifejacket of some sort to help you to float.
Essentially, it's used to try and keep you from getting hypothermia for as long as possible if you're stuck in cold water for an extended period of time. (And it definitely does exist!)