I use the DaKine windsurfing footstraps available at most cat or windsufring shops or maybe here in the online store. I only use one, at the back, but I race alone most of the time. They are adjustable and you can fit a foot in there while wearing booties.

It would have been nice to have another one for crew on the really windy days though, but going upwind the crew is further forward so I don't know how you would get to the inside of the hull to back the screws.