Good sleep hygiene is mostly four things: a consistent sleep and wake time, daylight early and darkness late, an earlier caffeine cutoff, and a bedroom that is cool, dark and reserved for sleep. Everything else is refinement. The twelve habits below all come from the CDC/NIOSH bulletin on sleep, and they are ordered by leverage rather than by time of day.

The reason this works as a checklist rather than a lifestyle overhaul is that the items are small and repeatable. Consistency is doing most of the work here, which is also why picking three and keeping them beats attempting all twelve for a weekend. For the biology underneath the list, see our complete guide to better sleep.

The 12-habit checklist

  1. Keep the same bed and wake times every day, including days off. CDC/NIOSH puts this first: go to bed and get up "at about the same times every day, including days off." The weekend is where most schedules quietly come apart.
  2. Get bright light during the daytime. Daytime light "strengthens your biological rhythms that promote alertness during work and sleep," so this habit pays out at both ends of the day.
  3. Make the bedroom very dark at night. The guidance is to block "any lights in the room (especially blue and white lights)." Standby LEDs count.
  4. Keep the room cool, around 65–68°F. CDC/NIOSH gives that range as comfortable "for most of us." More on why in the ideal bedroom temperature.
  5. Stop caffeine at least 5 hours before sleep. The bulletin says to avoid "caffeine, chocolate, and nicotine for 5 or more hours before sleep." Controlled research suggests even that may be tight, which we cover in how long caffeine affects sleep.
  6. Keep screens out of the last stretch before bed. The advice is not to expose your eyes to computer or phone screens before bed. A practical version of this is a digital sunset.
  7. Follow a relaxing routine, starting about 1.5 hours before bedtime. CDC/NIOSH suggests warm baths and dimmed lighting as part of it. The dimming is not decorative; it is the same light lever as habit 3, applied earlier.
  8. Use the bed for sleep and intimacy only. The guidance is direct: "Do not watch TV, read, or work in the bedroom." This is what conditions your brain to associate the bed with sleep rather than with alertness.
  9. Avoid alcohol near bedtime. It is on the list for a specific reason, and it is not the one most people assume. See what alcohol does to sleep quality.
  10. Get some exercise during the day. "Even a 10-minute walk will improve sleep," per the bulletin. The bar here is genuinely low.
  11. Finish exercise at least 3 hours before you plan to sleep. Same source, and it is the timing half of habit 10 rather than a contradiction of it.
  12. Avoid heavy or spicy meals within 3 hours of bedtime, and limit liquids for several hours before sleep. The second half of that is what stops a well-timed night being interrupted at 3am.

The core habits, ranked by leverage

If you only take three, take habits 1, 2 and 5. A fixed wake time gives your body clock a stable reference point, daytime light is the strongest input that clock responds to, and caffeine is the most common single reason an otherwise sensible schedule fails. Habits 3, 4 and 8 are the next tier, because they are one-off changes to a room rather than daily decisions you have to keep making.

Habits about light

Habits 2, 3, 6 and 7 are all the same lever pointed in different directions: light early, dark late. This is not a coincidence of the list. Light and dark are the strongest inputs to the body clock that decides when you feel sleepy, which is why four of twelve items concern them and why the circadian rhythm is worth understanding before you rearrange anything else.

Habits about timing

Habits 1, 5, 11 and 12 are about when rather than whether. Coffee, exercise and dinner are not problems in themselves; they become sleep problems at the wrong hour. This is the most forgiving group to work on, because nothing has to be given up. It just moves earlier.

Habits about the room

Habits 3, 4 and 8 describe an environment rather than a behaviour, which makes them the highest-yield items per unit of effort. Blackout curtains bought once keep working nightly without willpower. If your room is bright, warm and doubles as an office, fixing that removes three obstacles in an afternoon.

Habits people overrate

Three things absorb more attention than the evidence justifies.

Catching up at the weekend. Sleeping in directly undermines habit 1, the item CDC/NIOSH leads with. A long Sunday morning shifts the reference point your clock is working from, which is why Monday feels the way it does.

Optimising the sleep score. Research on consumer trackers has found their sleep stage estimates inconsistent against clinical monitoring, and clinicians have described patients whose pursuit of perfect tracker data made their sleep worse. There is more on that in our look at tracker accuracy.

Adding hours without fixing timing. The NHLBI's term sleep deficiency covers sleeping at the wrong time of day as well as sleeping too little, so more time in bed at the wrong end of your cycle is not a fix. If you are already spending long enough in bed, waking up tired anyway is the more useful thread to pull.

One boundary worth naming: sleep hygiene is a set of habits, not a treatment. CDC/NIOSH advises contacting a doctor if you consistently take 30 minutes or more to fall asleep, and persistent sleeplessness has its own recognised path, which we cover in why you cannot fall asleep. Working through a checklist for months while nothing improves is a reason to ask for help, not to try harder.