Our friend Dan Potts (Dan-the-Fisherman) has written these articles on how to tie and how to fish the Nuckols Fly Jig. He uses it to target smallmouth but it should also work for other species including trout and perch.

http://redrockadventure.com/images/fly-patterns/TyingNuckolsFly-PDF%207-20.pdf

http://redrockadventure.com/images/fly-patterns/Float-N-Fly-PDF-7-20.pdf