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Sleep schedules vary a lot from person to person. Some are naturally "larks"—early to bed and early to rise—while others are "night owls." Schedules shift with development, too, with babies typically being larks compared to older children; adolescents in particular often are on a later schedule, which can make it difficult to accommodate early classes.
Thankfully even night owls generally can align their schedules with the rest of the world. However, at times they may find themselves stuck in a cycle of late to bed, late to rise that's hard to get out of. For example, college students may go to bed and wake up later and later during winter break, and need to shift their schedule to one that's compatible with academics as the new semester approaches.
If you find yourself in this situation, here are some recommendations for effectively getting on an earlier schedule.
1. Start in the morning.
Most people who try to change their sleep habits start by trying to go to bed earlier. Since sleep has a beginning and an end, it makes sense intuitively that we should adjust the start time. Unfortunately this approach is very likely to fail.
The problem is that you won't have been up for enough hours in order to fall asleep easily, and so you're likely to lie in bed for hours; the next morning you'll probably stick to your typical wake time. There's also a good chance you'll get stressed out about not sleeping, which can lead to insomnia as your bed becomes associated with anxiety.
The better method is to think of being awake as having a start and an end, and adjusting when you start being awake. In other words, start by getting up earlier.
Ideally you can make this change gradually, so it's not too difficult. For example, if you've been getting up at noon, start by setting an alarm for 11:30 AM. Gradually shift your wakeup time 15-30 minutes earlier as your body adjusts.
2. Get natural light early in the day.
One of the most effective ways to shift your 24-hour internal clock (or circadian rhythm) is to have exposure to bright light at the right time of day. For moving to an earlier schedule, that means getting natural light early in the day—preferably as soon as you wake up.
It doesn't have to be for a long time (even 15 minutes helps), and you don't need the Florida sun—being outside on an overcast day or sitting near a south-facing window can be enough. The light will signal to your brain that it's time to be awake, and will suppress the production of melatonin, the hormone that tells your body and brain when to expect sleep.
On the flip side, avoid bright lights late in the day, like the glow of your tablet or phone, which can turn off melatonin production right when you need it.
3. Avoid caffeine later in the day.
If you're getting up earlier, chances are you're going to be sleepy at times during the day. The temptation to use caffeine to cope can be strong, especially around the mid-afternoon slump. However, it's likely to keep you awake at bedtime, pushing your wakeup time later and delaying your ability to change your schedule.
What's "later in the day"? A safe rule of thumb for most people is to avoid caffeine after lunchtime. If you're sensitive to caffeine, it may need to be even earlier. (Of course, if your sleepiness is a safety concern—like while driving—do what you need to do.)
Instead of caffeine, try something like going for a brisk walk or doing calisthenics. If you're able to go without it after lunch, you're more likely to be ready for sleep come bedtime.
4. Be careful about naps.
Napping can have a similar effect to caffeine, making it harder to fall asleep when you'd like to. Our drive for sleep depends on how long we've been awake, and naps reduce that drive.
As with caffeine, the time of the nap is important; a 7:00 PM nap is going to be a bigger problem than one at 2:00 PM. If you do nap, aim to keep it short—no more than 20-30 minutes. And again, nap for safety reasons when needed.
5. Go to bed when sleepy.
Finally, be careful not to go to bed too early. It's best if you feel like you could fall asleep relatively quickly once you lie down, to avoid spending a long period of time trying to wrestle your brain to sleep (see the first point, above).
On the other hand, you may be able to go to bed earlier than you think. Many people find that they get a "second wind" if they stay up past a certain hour, even if they were ready for bed earlier in the night. So take care not to push though sleepiness at night. By going to bed when your body is ready, you'll have a better chance of getting up when your alarm goes off.
Some individuals on a late sleep schedule could have a condition like a Delayed Sleep Phase Circadian Rhythm Sleep-Wake Disorder that may require consultation with a professional. As always, consult a qualified medical professional before making major changes to your sleep.
