My friend Tim recently asked for what to expect at a year 10 formal. He wants to know what's normal. I figure I would give some advice about dancing from an electronics engineer's perspective.
Dancing is all about standing waves, beat frequency oscillation, and destructive interference patterns (you do NOT want resonance, it will only look silly to have arms flailing at the same time as legs).

Stand comfortably, keeping a slight bend in your knees so as to have a marginally lower centre of gravity. Keep you feet about shoulder-width apart.

Move your left shoulder in a sinusoidal motion to the harmony of the beat if music is playing. Move your right shoulder pi radians (or 180 degrees) out of phase with your left. Leave hands by your side but in a semi-free swinging motion.

Make fist pumping or "raise the volume" hand motions iff (if and only if) every one else does.
You won't look like a dancing professional, but if you *do* feel inclined to dance, there's a formula that'll help you blend in. You *will* feel weird at first, but chances are, after you've had 2 or 3 songs of practice, you will *not* be the weirdest person on the dance floor.
Additionally... Nobody likes it when a guy makes the falsetto "ooh ooh" sound even though they pretend to. Don't be "that guy". :)

Hopefully that will help others out there who need dancing lessons in a hurry. While you *might* be able to learn to dance reall well in a heart beat, most of us can't. Best advice for someone who does not want to stand out is to try to blend in. Given most other people can't dance either you may as well treat it like Project Management. Under promise and over deliver. Set an achievable target and do it really well than set something a bit more challenging and mess it up royally.