You can do mouth exercises to get rid of chin jiggle.
One more time: You can't precision-target fat loss. It's just not possible to burn off the jiggle under your chin—or your arms or the backs of your legs or any other specific 5-inch-by-5-inch-square area. When you lose weight, you lose it all over your body, explains Matthew Berenc, director of the Equinox Fitness Training Institute. Some people may happen to notice more of a difference in the way that exercise makes their jaw or arms look, but it's in their genes—there's really nothing the rest of us can do to guarantee those results.