Searched the forums and didn't find anything on how to use a banjo minnow. Any advice or recommendations, or is it just a gimmicky lure

I get plenty of hits when I type "banjo minnow" into the search box. Try again, and you'll find tons of topics.

From the Forum Rules and FAQ:

I have a question about the Kicktail, Banjo Minnow, Doug Hannon Snake, Walking Worm lures, or the North American Fishing club

Do a search on the name. There's plenty of posts about it, which will answer your question.