Start black thread toward the back of a small dry fly hook.
Stack a small bunch of moose body hair (not moose mane) and tie it in as a short tail, about a body length. Use medium rather than tight wraps to keep it from flaring.
Tie in a small grizzly dry fly hackle off to the side at the rear, with a few wraps to lock the stem.
Cut a strip of 1.5 mm green craft foam, tapered slightly narrower at one end, and catch it in a couple of millimeters behind the tie-in point so it folds back cleanly, then squash it down.
Palmer the small grizzly hackle tightly forward over the shank — Savage skips a dubbed body entirely because the palmer is dense enough to cover it.
Fold the foam forward over the top as a humpy-style back, squash it down and secure it with a couple of wraps.
Snip the foam fairly close, leaving a small nub to bury under thread so it cannot pull free.
Tie in a second, slightly larger grizzly hackle at the front and take about three wraps for the collar — this is what holds the fly high and visible, since the foam keeps it buoyant but not floating high.
Wet your fingers, sweep everything back and build a small flat area for the whip finish, checking that the eye is clear of barbs before you finish.