How to Turn Your Bedroom Into A Sleep Cave

What You Tried: Light can inhibit the secretion of melatonin, the hormone that is your body's natural sleep drug, which is why turning off overhead lamps helps us feel drowsy.

What You Should Try: You can still detect even a small amount of light—from your alarm clock or your neighbor's garage—through closed eyelids. Champion sleepers tell us they've noticed that when they make their room pitch-dark, they wake up feeling more refreshed than when it's just inky-dark.

Black Out: Opaque curtains or blackout shades can block light from outside, especially from the new headlights and street lamps that use energy-efficient LEDs, which produce light in the blue part of the spectrum—the most sleep-sabotaging of all. Inside the room, clocks with red numbers are less disruptive than ones with white or blue digits; turn yours so it's facing away from you.