Heh, love the idea! First, make the audience think it’s just a harmless fireworks show—bright colors, sparkles, the works. Then, in the middle, swap a real boom for a fake one. Or hide a little device that shoots confetti and then suddenly explode a tiny fuse that goes off at the exact moment the crowd’s looking at the fireworks. Keep the timing off by a beat, like a jazz drummer—so it’s a surprise. Throw in a ridiculous contraption, like a “mystery box” that yells “BANG!” when someone opens it, but really it just releases a puff of smoke and a loud clang. The key is to make them focus on the glitter, then let the boom hit them when their eyes are on the glitter. Boom—chaos, baby!