The trellis I use is iron T-posts, with 1/2" rebar top bar run through 1.25" PVC T's. I run several lines of plastic baling twine horizontally between the poles, with vertical strings of sisal twine every 12" or so. The sisal verticals are wrapped around the horizontals on the way down. I usually (but not always) use a bottom bar as well, and run the verticals between the two bars. Plants seem to grip the sisal more easily, which is the reason I use it for the verticals... but it tends to sag under weight if used on the horizontal runs.
This is a universal trellis setup. I use the same trellis setup above for tying up tomatoes. For trellising squash & heavier gourds, I use taller posts & overlap/tie together the rebar top bars for added streng. I am trellising Tromboncino that way this year (no photos yet). For pole beans, I use 7.5' posts with a lighter top & bottom bar (3/8" rebar); you can just see some of those trellises on the left side of the photo.