I don't do kite surfing (that's the North Sea out there - people that work out there wear survival suits in the Summer, and you want me to go out there in my keks??), so that leaves little choice but to stand still and fly.
Enter the beach-skates.
Step 1: The concept.
Beach-skates are simple things - they provide a smooth surface to skid on, and can increase the size of your foot-print so that you do not sink so easily.
Step 2: Make the shoes.
That's it, really.
All you do is cut a hole in the side of the bottles, large enough to force in your normal kiting footwear*, then use duct tape across the top of the hole in place of laces, to stop the bottles falling off so easily.
I cut a large block-capital I shape to provide two large flaps that can wrap over the top of my boots.
If your boots are large (compared to the size of the bottles), you may need to cut a notch to accommodate the heel.
*Safety note - if your normal kiting footwear is low-sided, you run the risk of jagged edges cutting your feet. I normally wear boots.