[VFB] Tying legs

[J&A Burbank]

Hey gang, A rare serious post from me.  I'm looking to tie up some hoppers and would like to do some knotted PT legs. I've never tied any myself and would like a little advise on doing them. Do you use any flexcement on them? and is it easier to tie them on the feather vein or off of it?   Any help would be great   Jim