There’s dancing, and then there’s Thom Yorke’s arm-dancing — a purer form, all swirling hips and oddly angled arms. It’s a movement you can’t forget (especially if you have seen the “Lotus Flower” video or the just-released “Ingenue”). But it’s not easy to imitate! So in honor of Yorke’s latest musical project — Amok, a new album from his supergroup Atoms for Peace — Vulture has created the definitive guide to Thom Yorke’s Arm-Dancing. Study it now, and you will be totally fluent by festival season.