I built a platform out of saw horses, 2 X 12s, and a couple of sheets of plywood, and made sure that it was flat and level.
The kayak you see on the floor is a Pygmy, Arctic Tern. I bought her used at Portland Kayak Company and I loved her from the minute I first paddled her. There were two drawbacks for me with this kayak: One was that this Arctic Tern is a 17 foot touring kayak, built to haul a person and everything else including the kitchen sink. I really wanted a smaller “play” boat. And two, she was built by someone else. They did a fine job, but I saw things right away that I knew I would do differently (to put it as tactfully as I can). Also, every time I took her out on the water people would tell me what a beautiful kayak she is, and ask me if I built her, and it stung a little to have to tell them that I hadn’t. I knew after my first paddle that I was going to have to build my own or I’d never be able to look myself in the mirror.