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Layer 4 — Signal

Signal: your circadian rhythm and internal clock

Consistency and light timing are the strongest, most underrated levers in sleep — working with your body's clock instead of against it. — when to get light, when to avoid it, and why a steady schedule beats a perfect one night.

Daily light schedule with nodes coloured by time of day: on waking get 10 to 15 minutes of bright outdoor light, midday take daylight and movement breaks, afternoon keep it bright, two hours before bed dim the lights and cut blue light, bedtime sleep in full darkness.
Bright days, dark nights. Light is the strongest signal for your circadian clock. Front-load it in the morning and starve your eyes of it before bed.

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