Here's some stuff I reckon might help...

Make no mistakes. Each time you fall you lose a heap of ground.

Keep your kite steady and to the edge of the window. If you have to power dive a lot then you're probably only just keeping your line.

If you're really overpowered then keep the kite lower then the usual 45 degrees. It's a lot of pressure on the body but it will stop you getting pulled off your rail.

Don't use a board with too much rocker. Actually a lot more can be said for the type of board you use (rail thickness, outline, width, volume, surface area, fins....)

And the one that always gets me, stop jumping for a second! I can't help myself :P