According to the National Sleep Foundation, 99 percent of Americans have a sleeping pillow to rest on when going to sleep. So, if you’re that 1 percent of people who doesn’t sleep with one, you can safely disregard the contents of this article.

If you’re a part of that 1 percent, however (and you very much likely are), read on...

Figure out your sleeping style

Before you do anything else, even before buying a pillow, you have to factor in your sleeping style.

You’re either a back, side or stomach sleeper. Or maybe you think you’re all three… which on bad nights, that’s possible. The best way to make sure is to document what side you’re sleeping on when you get into bed and what side you wake up on.

We go into further detail about ideal pillows for the type of sleeper you are here. The main thing is that you’re looking for a pillow that gets you to a good sleeping posture to avoid the neck pain due to a pillow mismatch. “A good sleeping posture is key to sleeping soundly, night after night, and to waking without pain and stiffness,” says Michael Breus, clinical psychologist and sleep expert.

Give your sleeping pillow a test run

After you’ve figured out your sleeping style, what’s next is finding the pillow that’s compatible with your style. Whether you already have a pillow or are searching for a new one, try these tests:

• Sleep on it! Get to sleep, wake up and make a log of whether or not you had one long continuous sleep or if you woke up intermittently. There are obviously other facts that could prove to be disruptive to your sleep—hot sheets, impressively loud snoring partner—but things like neck pain usually point to a bad or incompatible pillow.

• If you’re in a store and looking for a new pillow, try this piece of advice from Breus: pretend people sleep standing up. Align yourself against a wall with your sleep style (stomach sleepers, for example, would be face first with the wall). Press yourself against your test pillow and ask another person if your neck’s in line with your spine. If it is, then great! There’s a potential for a real relationship here between you and sleeping pillow. 

If you'd rather not make the time go to stores in-person, you could also order pillows from ecommerce retailers to see what sort of pillow trials are on offer. Generally, you should find pillow trials with 100 nights free and a no-questions-asked return policy like ours.

Replace Pillows When it’s Time

The common consensus is that sleeping pillows should be replaced every 18 to 36 months. The National Sleep Foundation and Tuck peg it around that timeline. There are a lot of problems that come with the longer you use a sleeping pillow. Some of that is covered here.

The longer you keep a pillow, the more it loses its structure and its ability to keep away from morning neck pain. And it gets more gross—your dead face stuff winds up on the pillow. So if you have the means to avoid all that, keep a regular schedule of pillow-replacing.