Bergal1,
Jigging Raps glide or plane outward on a slack line. To achieve this, I smoothly lift up, then abruptly drop the rod tip to give it slack. The lure plunges down and away from the hole. When the straightened line checks its descent, the lure swivels and returns to a position beneath the hole. It's a wandering lure, but it's leashed. The distance from the hole that it swims is determined by the length of slack line it's been given. If you only lift-and-drop a few inches, the lure noses out only a short way and then returns to true. I think this is a good mimic of a small baitfish.
The retrieve or cadence, though, is up to you. There are many possibilities. I prefer a lift of less than 12", followed by a drop. I pause as the bait executes its maneuvers, waiting and watching for a strike. Fish are often slower in cold water, so I give it a few seconds before starting over. You can also just make them shiver in place; sometimes that works.
I use the smallest two sizes, mostly, and perch crush these things. Crappies and panfish respond pretty well, and I've caught pickerel on them, too. I know trout will take them, also bass. They're effective tipped with bait or fished plain.
When fishing shallow in the weeds, I've noticed they have a tendency to reach out and snag weeds some distance from the hole.
