Especially in the spring or anytime crappies hold in shallow water or around shallow brush or grass, I'll fish a float with a small jig at least three-fourths of the time. I prefer a sliding balsa (slip) float, which can be adjusted to hover a bait at any depth. The addition of a stop knot or bobber stop on your line, with a tiny plastic bead between the float and the stop is the simplest way to fish a float. For fishing shallower than three feet, a small, fixed float or clip-on style bobber also excels.  The key is to properly "load" the float with a jighead and additional pinch-on or split-shot sinkers. The objective is to make the float sit upright in the water, stem just barely protruding above the surface, so it's visible and nearly effortless for a fish to submerge. When crappies feel little or no resistance, they're much more likely to eat and hold the bait, signaling a strike and yielding a successful hookset.