I’ve been told that I should use vertical jigging when the Walleyes are below 15 feet. Can you tell me how this works?

Actually, vertically jigging works well for Walleye that are hanging together in water that is any deeper than 8 feet.  As the name implies, vertical jigging is simply presenting the jig directly beneath the boat and hopefully right in front of the fish.  It can be effective in both rivers and the deeper areas of a lake.  You’ll want to use a jig with a round head and a long shank hook which will up your changes of setting the hook when you pull it vertically.  Positioning your boat directly over the area you want to fish, lower the jig into the water slightly above or right at the depth you think the fish are holding.  Pump the tip of the rod up and down.  You want to lower the rod quickly enough that the lure drops freely but you’ve got to be careful that you’re not adding any slack to the line.  I’d suggest pumping the tip anywhere from 6 to 24 inches.  Be prepared for the strike on the drop of the rod.  There are quite a few lures that are popular for vertical jigging but I believe jigs and spoons work the best.  If you’re not having any luck, you can try adding a live minnow or nightcrawler.