There are many ways to fish jigs. The easiest method is to tie one on, cast it out, and slowly reel it in. That’s a good way to cover lots of water. A lot of flounder pros stake out their boat on a likely spot, and fan-cast a jig, swimming them along the bottom. If they catch a couple of flounder, they switch to a slower retrieve, in order to precisely and thoroughly work all the water within casting range.