One tactic is to keep on the move when casting, pitching or jigging. To move fast, use a 1/8- or 1/4-ounce jig. Tip with a small minnow. The rig allows a fisherman to quickly get to the strike zone, feel everything the jig touches and get it back out to drop into another spot. The minnow draws more strikes.
Typical mid-states and southern crappie will likely be in six to 18 feet of water. It varies with each lake or river and also with water temperatures. Stay above the thermocline. If no thermocline, check all depths to find the most active crappie.
Last tip: change minnows often. A lively, small minnow will attract more fish. –TH