There will be a plywood deck covering the forward floatation chamber and the partner, and extending on the sides about 12" aft of the partner. Here I am making a pattern for the deck using a "Joggle stick." I will explain joggle sticks in a later post, but right now it is past my bedtime.
I used the joggle stick and marking board to lay out the curves on the sides of the deck. I have become smart enough to make a mockup from cheap underlayment, before cutting expensive marine plywood.
Then I cut out the deck mockup. I used a circular saw with a brand new sharp plywood blade to cut the curves -- a circular saw does not always have to cut straight. The sabre saw in the photo was used only to make notches for the stem and #1 frame.