It’s time to review a common travel problem: How do you fall asleep on a crowded airplane? Here are some tips from Dr. Jeffrey Ellenbogen, the head of sleep medicine at Massachusetts General Hospital:

First: Stick to your normal eating routine. Experts say your circadian clock affects your internal organs. So, have breakfast, lunch, and dinner at the same times you normally would.

The next trick for sleeping on planes: Wear clothing that allows your body to “breathe.” Research shows that in order to fall asleep, your body needs to release heat.  And the best fabrics for that are cotton or wool. In fact, that’s why Dr. Ellenbogen says you should avoid using the blankets most airlines provide, since those tend to be made of polyester, which traps heat.

Here’s another sleep trick you may not have considered: STOP thinking about your destination. Our expert says whether you’re excited about traveling somewhere new, or you’re stressed about a business meeting when you land, your mood on a plane can wreak havoc on your sleep. So, consider bringing a book to read, so you don’t dwell on what you’ll be facing when you land.

The next trick: Recline your seat. According to a study from the University of Pennsylvania, if your seat is recline 40 degrees, you’re more likely to sleep. If you don’t recline, you’re more likely to stay awake.

Finally: What about using sleeping pills on planes? Dr. Ellenbogen believes the noises you encounter on a plane are too much to allow “deep” sleep.  So, while sleeping pills can help make you drowsy, he says don’t expect miracles.  And they may not have worn off by the time you land, which will make driving or any other activity dangerous. So you’re better off not taking them.