Slide a 2.4 mm tungsten bead onto a size 16 curved 1X short nymph hook and put down a few wraps of .015 lead-free wire behind it. The fly does not really need the weight — the wire holds the bead in and bulks the thorax for a better taper.
Start the black 70 denier, build a small dam behind the wire, take a few turns over the wire itself, then run the thread back to the bend.
Unspin one strand of red wool yarn into its finer strands and catch a very sparse sliver in at the bend — just a hint of red, sitting round the bend. Trim the butt off.
Snip the brittle inch off three or four peacock herls and tie them in by the stiff ends just ahead of the tail; bury the butts, then take the thread back to the tail.
Pull four or five inches of thread off the bobbin, form a loop and secure it at the tail. Lay the herls into the loop, spin it into a rope with your fingers, then add a few more twists with hackle pliers.
Wrap the herl rope forward to just behind the bead, adding a twist every two or three wraps because each wrap takes one out. Tie off and snip.
Trim the red tail to final length — less than one hook gap, a tiny sliver.
Prep a small grey partridge feather: pull the fluffies off and make a tie-in point on the stem. Either leave it whole and make one wrap, or strip the fibres from one side and make two.
Tie it in behind the bead and take one full turn with hackle pliers, starting at the top and stopping at the top, then two wraps to secure it and trim the stem. The fibres should reach well past the hook point.
Take a few more turns to lay the fibres back and even the collar, then close with two three-turn whip finishes behind the bead and snip any strays.