When flounder fishing with hook and line, many anglers prefer using a jig with a plastic tail that resembles a shrimpor minnow. Live or cut bait can also be utilized with a jig head, as can an effective additive such as Cotee's Tippit or Bait Shapes product.
Some anglers prefer a slip sinker rig when using live shrimp or baitfish.
When using the slip sinker rig cast your bait and let it sit on the bottom for a couple minutes. If you don't detect a pickup lift the rod tip and let it sit again. If a flounder picks it up you will feel the line being pulled slowly out, give the flounder line so it doesn't feel the weight of the sinker. This is the hard part, don't set the hook instantly, give the fish time to get your bait into its mouth. A count of thirty is usually a long enough time, before you take up the slack in the line and set the hook.