If you have a tough time falling asleep when you travel, you need to know about melatonin. This hormone, churned out by your brain’s pineal gland when night rolls around, slows body functions and lowers blood pressure, basically setting the stage for sleep. The problem is, traveling—especially if you’re jumping time zones — can interfere and set the stage for insomnia. Head that problem off at the pass with this advice.

When you pack: Bring melatonin supplements. In a study published in the journal Sleep, researchers found that people who took as little as 0.3 milligrams of melatonin got about a half hour more snooze time. Check with your doctor about the right dosage and timing for you.

Before you go to bed: Go for low light. In your room, switch off any overhead lights, and turn the TV (and your laptop, tablet, or smartphone) off. The darker your bedroom, the more melatonin your brain produces. Want to read before bed? Clip a low-power reading light directly onto your novel.

After you get up: Get bright, fast. Daylight signals the body to suppress melatonin production so you can remain alert and awake; it also helps reset your body’s internal clock so you can fall asleep at a usual time. For a morning dose of alertness, get some direct sun exposure for 30 minutes within one hour of waking. Not possible? Amp up the lights in your room and open the drapes to let in any natural light.