Dave, just look at the back of a snakey stave,there will be no doubt how to lay it out.You just have to follow the grain pattern from one end to the other ,and try to visualize the bow in the stave.Make sure you have plenty of width,outline the tentative bow with a pencil, before making a cut. I usually outline one side,careful to follow the grain,from tip to tip,then draw the other side,keeping it parallel with the first side drawn,then make adjustments where needed ,and then work out your taper to the tips. Hope this helps, God Bless