Found an unattributed pic on the interweb; swapped out the Krystal Flash underwing for Ice Dub and added some rubber legs because they go so well with foam (if you skip the legs, oversize the hackle). On anything #12 or smaller, I'd switch to 1mm foam.

hook - Dai Riki 135 #8
thread - UTC 140 rusty brown
rib - tying thread
body/shellback/head - 2mm foam tan
underwing - Ice Dub pheasant tail
wing - deer hair
legs - medium rubber brown (optional)
hackle - ginger

Part 1

poke a hole in the foam




mash barb, slide foam onto hook, start thread, wrap halfway down bend




move foam back to thread, tie down






brush shank with Super Glue, move thread up; tie down foam creating 1st segment




repeat




when you reach the 3/4 mark, tie off/trim foam




pull foam forward over hook; tie down, wrap to eye