Start the orange thread one eye-length behind the eye and wrap a smooth thread base back to the start of the bend.
Tie in a brown rooster saddle hackle by the butt at the bend, shiny side facing you, and let it hang rearward.
Cut a strip of orange 2 mm foam about half a hook gap wide and tie it in at the bend with several firm (but not foam-cutting) wraps; advance the thread to one eye-length behind the eye.
Wrap the foam strip forward in slightly overlapping turns to form a buoyant, gently tapered body; tie it off at the thread and trim the excess.
Palmer the hackle forward over the foam body in five or six evenly spaced turns; tie off in front of the body and clip the tip.
Clean the underfur from a pencil-sized bunch of bleached elk hair, stack the tips even, and measure the wing so the tips reach the far edge of the hook bend.
Tie the wing down directly in front of the body with several tight wraps, letting the butts flare over the eye; trim the butts to a short, blunt caddis head.
Whip finish under the elk-hair butts, clip the thread, and add a small drop of cement to the wraps.