If you’ve been plagued with sleeping problems, you already know the basics of what should fix it. You know your bedroom should be dark and cool. You know you should read a boring book before bed instead of answering work emails on your phone. You know pouring that nightcap is probably going to mess with your REM later. If none of this is breaking news to you and you’re still having trouble sleeping, you’ve come to the right place.

We asked renowned sleep doctors for a step-by-step plan for how to fix your sleep once and for all, whether you’re recovering from recent timezone-changing travel or you haven’t gotten consistent good sleep in years. With the steps outlined for you, you’ll find that fixing your sleep isn’t as overwhelming as you probably think.

What does optimal sleep look like?

Before you make over your sleep schedule, it’s helpful to know what your end goal should be. What does having a healthy sleep life actually look like? Major Allison Brager, PhD, an active-duty neuroscientist, sleep expert, and assistant professor at West Point, says that optimal sleep means getting between seven and nine uninterrupted hours at night. She explains that some people only need six hours while some need the full nine; it depends on the person.

Wissam Mansour, MD, a sleep medicine specialist with Duke Health, adds that “a universal ‘one‑size‑fits‑all’ sleep rule doesn’t exist because individuals vary in their sleep needs and circadian timing.” That said, he says most adults function best with seven to nine hours of sleep a night, with consistent bedtimes and wake times.

Dr. Mansour emphasizes that a consistent sleep schedule is essential. “When sleep timing fluctuates, the circadian system becomes misaligned, which can lead to fragmented sleep and difficulty falling or staying asleep,” he says. That means that your weekend sleep schedule shouldn’t look all that different from your weekday sleep schedule.

Sleep medicine doctor Domingo Rodriguez-Cué, MD, says that how you feel during the day also matters. He says that if you spend nine hours a night in bed but you feel like crap during the day, something is up. With this in mind, having good sleep means getting between seven and nine hours of sleep a night consistently, and also feeling energized throughout the day.

How to fix your sleep schedule after a short-term disruption

Even short-term disruptions in sleep can impact health. Dr. Brager says that daylight savings time is the perfect example of this. “The day after we ‘spring forward’ and lose an hour of sleep, there is an increased rate of sickness, heart attacks, and accidents the following day. Believe it or not, losing that one hour of sleep can be the tipping point for many people,” she says.

Scientific research as far back as 1996 and published in the New England Journal of Medicine have shown this to be true. More recently, a 2019 study published in the Journal of Clinical Medicine has found a link between daylight savings and increased risk of heart attacks.

This means that even if you’ve experienced a short-term disruption in sleep—due to travel, a booze-filled bachelor party, or pulling an all-nighter for work—it’s important to get back on track. All four sleep doctors we talked to said that strategically timed light exposure is the most effective way to do this. Dr. Rodriguez-Cué says that this means getting sunlight exposure in the morning and using dim lighting in the evening. This, he says, will support the body’s natural process of releasing melatonin in the evening, which signals to the body that it’s nighttime, which leads to feeling sleepy.