Before I begin the finishing process, I usually block my quilts (not shown) by dampening them, laying them flat on a pinable surface(eg. a big board ironing board for smaller quilts) or a solid but slightly soft surface ( like carpet covered with a clean bed sheet). Once dampened, and smooshed ( "technical term"..not really ) flat, the quilt is pinned along it's perimeter and allowed to air dry. Once dry and flat... as IS shown here, I measure and mark the intended edges of the piece. In this example, I again used a Frixion Pen and ruler for straight line marking. "Don't be afraid to eliminate some area (as in the top of the piece below) if it ultimately doesn't seem to add anything positive to the cause.. or also as in this case, it seems distracting.