Wind on a number of turns of lead wire, depending on the depth of the water to be fished and fix into place with the thread.

Tie into place the tail.

Tie into place the turkey feather, that will form the wing case.

Dub the thread with green Muskrat, but first cut the guard hairs down or out.
Wind on and increase the size of the dubbing under the wing case area.

Pull down the turkey feather to form a wing case and tie down.
Pick out the area under the wing case to form legs.

Trim all the Muskrat to form a semi smooth body, with only legs showing.
This pattern uses the hook's eye as part of the nymphs head.

Little useful trick, colour the heads of your nymphs with different colours to indicate the amount of lead, the depth the fly is designed for.