Hands: so useful, yet so problematic! What to do with them? Shove them into pockets? Use them to clutch the sides of the lectern with last-lifeboat-off-the-Titanic fervor? Flick away invisible flies?

We know we do it. But have you ever studied a person’s gestures as they spoke to you? Or noticed how you move your hands subconsciously when speaking? Gesturing comes naturally to many of us and is ...