I've seen jigs fished a couple of ways, one way is to fish it without a float, usually 1/8th or 1/16 oz marabou jigs (no trailer). Toss it out, let it sink to the bottom, then rip it off the bottom a foot or two, let it sink again, repeat until you work it back. Zig jigs (zigjig.com) are great for this technique.
I've seen very light jigs (1/32 and smaller) fished under a float. Do some searching in the Taneycomo forum and I believe you will find some posts by Phil Lilley talking about fishing them that way.
White river forum has posts on fishing Zig jigs.