Here is a picture of a Cigar Minnow.
It's not a "minnow" like you would find in fresh water. It's just called that I think because it is a relatively small fish, 5-6 inches long. You catch them (usually) on a Sabiki rig or (my preference) Gold Hook Rig. The GHR is just 3-6 small gold hooks spaced about 6 inches apart on your line above a weight. I think the flashing gold hoos look like wee little shrimps or something to the Cigar Minnows (and other bait fish as well). It can be a real hoot to hook up several bait fish on a GHR at once since they are all going in different directions.
You should have a bucket of salt water ready to put the bait fish into to keep them lively. If there are plenty of bait fish but nothing bigger biting you can put the bait fish into a plastic zipper bag (you do bring some of those with you don't you?) and take them home and freeze them. These make great baits (cut in half) for snapper at night.