Here's a simple caddis tied with a modular, spun needle body. Spin a waxed #12 beading needle at high speed (Nor vise etc). Touch some fuzz to the spinning needle. Instant body. Soak it with Aleene's Flexible Stretchable water based fabric cement. Pinch the body while spinning it some more.
Tie on a down wing (still on the needle) facing forward. Pull it back. Wrap twice to form a small head. Whip finish. Pull it off the needle. Trim fore and aft.
Put a hackle on a scud hook. Mount the modular body loosely at mid-shank with very little tension on the thread. Wind the hackle between body and shank, so you end up with a bottom-mounted-parachute.
Wrap twice from BEHIND to pinch the tip of the hackle, so the thread butts up against the bend of the hook and slides up to mid-shank. Whip finish twice the same way, using the bend of the hook.
Trim thread and hackle tip with a razor. Everything is only loosely bound at this point. Put a dab of glue (almost any glue will do) at the fulcrum of the parachute to fix all loose ends together permanently.
Call it a wrap. Sits low close and flat to the water like a real Caddis. But it floats like a cork. These are champion floaters. When you mend the line they often skid across the surface rather than sinking.