On the rear hook, tie in 3-4 olive ostrich herls at the bend for the tail appendages, then wrap an olive D-Rib abdomen forward for a segmented, translucent body; reserve the herls along the sides as gills and tie off. This hooked abdomen links to the front shank with a loop of mono so it wiggles side to side.
Mount the front shank, run the mono connector back to the rear hook, and lock it down along the shank.
Continue the D-Rib body forward over the shank, drawing the reserved ostrich herls up the sides as gills, then tie off.
Slide or tie a small bead under the front of the shank so the fly dives nose-down when it pauses.
Tie in a CDC feather and fold it back along the sides as long, mobile legs.
Fold a strip of olive-tinted medallion sheeting over a short dubbed thorax as a wingcase, tie down at the eye, whip finish and cement.