Mattresses are a long term commitment: They last about a decade. So when you go to buy a new one, you really don’t want to screw it up. We spoke with Rick Maynard, Senior Manager of Public Relations and Corporate Communications at Tempur Sealy International, at an event for Cocoon by Sealy mattresses to find out the best way to pick a new mattress.

1. KNOW THE SIZE OF YOUR CURRENT MATTRESS.

Mattress shopping starts before you even make it to the store. First, you should measure your current mattress; then, measure the room you’re sleeping in. That way, you can get a bigger set without worrying if the bed will fit.

2. DRESS COMFORTABLY—AND BRING A PILLOW.

The best part of buying a new mattress is testing your options—and to do that, you need to be as comfortable as possible. We’re not saying you should wear your pajamas; but if you did, no one would judge you. Maynard also recommends bringing your favorite pillow along.

3. PREPARE TO SPEND SOME TIME TESTING MATTRESSES OUT.

The biggest mistake consumers make, Maynard says, is not spending enough time choosing a mattress. “They just sort of give it the hand test or sit down and bounce on it and then say, ‘Well, I’ll go with that,’” he says. That is a surefire way to end up with a mattress that doesn’t work for you in the long run. “You’re better off spending more time on the front-end,” Maynard says.

4. ACT LIKE YOU’RE AT HOME.

The key, as you may have figured out by now, is to make your mattress testing experience as close to going to bed in your own home as possible. Break out that pillow and “lay in the bed like you would sleep in the bed,” Maynard says. “If you’re a side sleeper, don’t lay on your back.”

Same goes for if you’re shopping with a significant other. “It’s really fun whenever you see a couple come into a retail store and they end up spooning,” Maynard says. “People may snicker, but that’s the smart way to shop, because you have to find out if this is going to work for you.”

5. TRY OUT A VARIETY OF MATTRESSES.

First, figure out what comfort level you want: Are you a fan of a soft bed, or a firm one? (Many manufacturers have varying levels of plush and firm, so make sure you test them all.) Once you’ve got that figured out, try all the different mattress technologies—innerspring and latex and memory foam—before making a decision.

6. IF YOU DON’T LIKE WHAT YOU’VE PICKED, DON’T BE AFRAID TO RETURN IT.

Return policies vary by retailer, but many companies that sell mattresses over the internet offer trial periods. Customers who buy Cocoon mattresses have 100 days to test out the bed, so if you originally opt for the soft but find you’d prefer a firmer mattress—or vice versa—you can exchange it. “Bring it home, get to know it, and if it’s not exactly what you like, you call us, and we’ll bring you the other one,” Maynard says. Returned mattresses aren’t resold; they’re either donated to charity or recycled.