Walk back on your board until you just about sink it - sail downwind, lean your mast, sail is crossways to the board - wait til sail feels weightless, then let go with back hand, cross back hand over to the other boom, let go with front hand.

trick in carve gybe is to sail really fast, then turn downwind, once you're downwind, sheet in really tight, take back foot out of footstraps, wait until you're almost sailing clew first, then once youre just about around the turn, let your sail go, and it will flip around and you're sailing the other direction.

First pioneered by Naish
12 O'clock is straight upwind, 6 is straight downwind.
You start out sailing at 9 - crossways to the wind.
Unhook the harness lines, without changing the direction of the sail, or putting pressure on the board - don't let your gear know you unhooked. (you were harness steering).
Gybe moves from harness steering, to sail steering to board steering.
So - first, have to be sailing fast enough, on a plane.
Look ahead to where you are going to turn - to check that way is clear and to decide on the point at which you will gybe.

Take back foot out of back footstraps, put it beside the front foot, keep front foot in.
unhook the harness lines, without changing the direction of the sail, or putting pressure on the board - don't let your gear know you unhooked. (you were harness steering).
Unhook the harness lines, while keeping the sail steady - keep pressure on the boom, not on the board.
Keep sail sheeted in and pressure on the rail, to carve the board slightly downwind.
To keep sail sheeted in - arms are in "bow and arrow" - keep back elbow bent, front arm straight along the boom.
Press down with the lead foot - the one that's in the footstrap. heel up, pressing on the ball of the foot - start to turn the board downwind.
Centre the mast with the horizon - 90 degrees, let the back arm out a little, and sail on a broad reach - very briefly.
Then when you're about 1 hour off 6 oclock, step, step to the other side of the board, tilt the mast and carve with both feet on the other rail, sailing clew first until you're aboout 1 hour off 6 oclock the other direction, keeping the speed up, then flip the sail (when it starts to feel weightless) - let back hand go - cross hands so back hand becomes front hand in other direction - if you're sailing with over hand grip, change sides by reaching back arm over hand on front of boom and grab underhand to sail the other way - if you're sailing underhand, flip and grab overhand and sail on a broad reach, until you get going again.