Slide the Bead (a 2.4 mm tungsten, slightly undersized for the size 12 2X-long nymph hook) to the eye, then take about 10 wraps of the 0.015" lead-free Weight and jam them tight into the back of the bead to lock it.
Start black thread behind the weight, bind over it with a few wraps, then run the thread back to the bend.
Snip four Brown goose biots. Take two, flip one so they sit back to back and splay apart, and tie them in long at the bend with a pinch wrap. Cheat them toward your side so that if they roll under thread pressure they roll onto the top. Add a few securing wraps and check they stayed on top.
Bind the biot butts forward with loose wraps to just behind the weight, then add a few extra wraps to smooth the underbody.
Catch in the Brown hackle (a rooster dry-fly feather, fibers reaching just past the bend) at the rear, tip pointing back, leaving a short length of bare stem exposed so the first turn lays no fibers. Snip the excess.
Tie in three or four strands of Peacock herl at the bend and park the thread just behind the bead. Wet your fingers and spin the herl into a loose rope, then wrap it forward to the bead. Tie off, snip or break off the excess, and add a few locking wraps.
Palmer the hackle forward in close turns to the bead, tie it off, and snip the excess. It will look far too bushy at this point.
Trim the hackle flush across the top and hard down both sides so the only fibers left are the ones hanging below the shank as legs.
Take the remaining two Brown goose biots, leave both concave side down, line them up in a V over the back, and measure them as a wing. Seat them with two loose wraps, adjust the position, then add about four careful tight wraps.
Push the biot butts up and bury them under thread, building a smooth base between the bead and the wing. Whip finish, then put a drop of head cement on top of the bead and let it wick down into the thread wraps.