Securing the edges of the hull when launching the Sunfish

I was wondering, how do you secure the edges of the hull when launching the sunfish into the water?

In my case (ahead of Sunfish delivery), in our marina, there is a slope for dinghies which helps with launching. Normally you would go down with the dolly, put your dinghy in the water, join it temporarily to the wooden platform (with wooden side panels), take the dolly back to its place, and then return to the dinghy. The problem is that when you are away, the dinghy (or Sunfish in this case...

Securing the edges of the hull when launching the Sunfish