I’d layout exactly as it looks, let it overlap as it travels in the z (assuming we are looking at it from top view) and then extrude edges straight down, convert to nurbs and trim to clean it up at the end. (keep a subd copy for future iteration)
try this as a quick reference. Bevel edges instead of creasing to have sharp edges that aren’t razor sharp.
or, convert creased model to nurbs and fillet later.
scroll.3dm (125.3 KB)