Hey Getfunky,
Start off by pulling on one of the outside lines by about a metre, usually the opposite of the side you want to launch on, and hold this in tension as you swim in the direction of the side you have pulled on. The tension will start the kite moving to one side of the wind window and you simply swim in the opposite direction to help it out on it's way to the left or right side of the wind window.
Next step is to quickly (before kite moves straight downwind again), grab the centre lines above the trim strap and give a solid yank as far back as possible behind your head then swim like a fish at the kite, the whole while keeping tension on the side you originally started pulling tension.
The idea of this method is that if the kite is off to one side of the wind window, then when rolling it on it's back whilst it favours one side of the window it will be really easy to get it to roll and move to the edge of neutral for a normal takeoff. If you have any twists in the lines, remove the twists before you pull the kite out of the water as a twist in the lines pulls additional back line tension on the kite which oversheets it forcing it into a possible stall on takeoff resulting in the kite falling back on it's trailing edge and you having to start all over again.
Hope this helps,
