The best book I’ve read on sleep is Matthew Walker’s Why We Sleep . In it, he explains the importance of getting good sleep as well as offers suggestions for how to avoid problems of nighttime insomnia.
Here are a few strategies you can apply to sleep better:
1. Reduce light levels (especially blue and white light) before bed
The body uses two different hormone systems for signaling the need to sleep. One of these is managed by melatonin  and is influenced by light levels. This creates our circadian rhythm of night and day. It’s also responsible for jet lag, as our mental clock is out of sync with the actual clock, resulting in struggling to sleep at night and napping all day whenever you have to travel overseas.
This melatonin system is influence by light. Unfortunately, in our modern environment we are constantly illuminated by bulbs and screens, making it easy for this system to get out of sync.
Tip: If you struggle getting to sleep early, make it a habit to use minimal lighting (or no lighting) an hour before bed. I often listen to audiobooks in a mostly dark room as I try to fall asleep. Avoid LED screens which have more blue light, and are more likely to trick your brain into thinking it’s daytime.
2. Avoid caffeine after noon (including decaf coffee)
Caffeine interacts with the second of the two hormone systems our bodies use for sleep. As we go longer without sleep we accumulate adenosine. Receptors watch for levels of adenosine and push us to sleep when it has been a long time without shut eye. Caffeine, in turn, temporarily “plugs” these receptors so they can’t deliver the sleep signal they normally would.
The problem, however, is that caffeine doesn’t actually remove adenosine from your body (or give the restorative benefits of sleep), so when it finally breaks down, all the adenosine that was present before comes back and can make you feel worse than before. Sometimes, this can lead to the urge to have a second cup (or fourth) in the afternoon, to push through the rest of the day.
Unfortunately this can also interfere with later sleep. Caffeine loses its immediate kick soon, but it has a surprisingly long half-life in the brain, meaning even hours after drinking it, there is still a non-trivial amount in your system. Decaf coffees, while having much less caffeine than normal, still have non-trivial amounts of caffeine, so a decaf after dinner might also make it harder to sleep.
3. Sleep the same time on weekdays and weekends
I know, I know. Easier said than done. Weekends are a good time for socializing, and who wants to be the person going home to bed at nine pm?
Still the benefits of a consistent sleeping schedule may make up for the occasional social interference. Staying up late, especially if you struggle to sleep in fully, can mean you’re not getting a full night’s rest on weekends. This is particularly true if you drink alcohol before sleeping, which can interfere with the brain processes of sleep that make it restorative. Do this regularly and it’s no wonder you’re always exhausted.
Sleeping habitually at the same time is a good way to prevent missing sleep.
4. Watch out for naps
If you struggle with falling asleep (or staying asleep) then the fatigue can push you to take naps in the day. However, as Walker points out in his book, napping can alleviate some of the adenosine build-up, which conversely, makes it harder to fall back asleep at night time.
I certainly struggle with this advice myself, as I often take quick naps in the early afternoon. I do think a short nap (15-20 minutes) is preferable to a long one, if only because it has a lesser impact on later sleeping.
5. Get help from your family
For some, going to sleep is an entirely independent choice. However for many of us (myself included) going to sleep usually means going to sleep with your spouse (or having them come in after while you’re already trying to sleep). Therefore, when working on a new sleeping habit, it’s important to communicate your goals and motivations. If you don’t talk about it, then the habit likely won’t last as you stay up to watch another episode of Stranger Things.