Consider trying a technique similar to "paper piecing" that quilters and stained glass workers use

Cover your forms with a layer of paper. You can use multiple smaller sheets, or a single long piece of butcher paper or newsprint. Cut darts in this, and glue it where necessary to get a nice snug fit to the forms. A staple or a drop of glue here and there will hold it in place.

Draw out your design on this paper using pencil. Pens or markers may bleed during the construction process.

Now you have a full size template in the proper location, and you can cut your strips to line up with the lines you've drawn on the paper. Small sections of inlay, or other little pieces can actually be hot glued to the paper to keep them in place while other pieces are arranged around them. The paper is strong enough to keep the little pieces from falling down. Should you need to get under it, though, you can easily slit it to give access.

You can use this over just a small area, or over the entire deck.

The paper is too thin to make a difference on the thickness of the strips laid on the forms or the lines of the boat.

Hope this helps

PGJ