A tow buoy is the cheapest way to stop being invisible to boats — but the moment you clip one on, you're towing several metres of rope around your fins. Here's how to rig one for the kind of snorkeling where nothing goes deeper than about five metres.
Going from floating on the surface to gliding a few meters down looks effortless when someone else does it — but there's a small sequence of moves, and one counterintuitive safety habit, that make the difference between a smooth descent and a mouthful of seawater.