I just started fishing them this spring for walleyes. I mostly fish them on a jig head and cast current brakes and other current areas where walleyes should hang out. My method I'd to match the weight to the current and depth so that I get a slow fall on a somewhat tight line. When it hits the bottom I pick it up and let it fall again picking up slack line as I bring it in. The hits usually occur on the drop but they will pick it off the bottom as well.
Another way I fished them with good success was Texas rigging them when there is a lot of wood around. Same technique just helps keep you from getting snagged.
I'm sure they would work vertical as well just haven't tried yet.