WINTERIME IS SLEEPWEAR’S big season, with half of all sales occurring in the final quarter of the year, and it’s really no surprise: few things feel better than slipping into some comfy, cozy pajamas at the end of a cold, exhausting day.

Warm sleepwear is even good for your wallet, because it’s cheaper to heat the person than the house. With the right bedtime clothes, you can dial down the thermostat and still stay toasty on chilly nights. However, Santa-print flannel sets aren’t an optimum sleep solution for everyone, and it can be overwhelming to make the best choice about what to wear to dreamland. We’ve put together a guide to cold-weather sleepwear that will simplify shopping for bedtime duds.

Take a Cue from Campers

To stay extra-toasty on a chilly night, think like someone who’s outdoors and roughing it. Plenty of camping enthusiasts spend the night outdside in all weather, and while choosing the right tent and sleeping bag is important, sleepwear is also a vital component of their gear.

Campers follow a couple rules of thumb when outfitting for bedtime. Avoid cotton, especially thick weaves like flannel. It absorbs water, holding sweat against your skin rather than wicking it away. Combine that with the fact that cotton isn’t a good insulator and you’ve got a recipe for a clammy wake-up.

Wool is a better choice because it pulls sweat away from your body and insulates even when wet. Merino, a soft, lightweight variety of wool, is especially good. Socks are important, too, since your extremities tend to lose a lot of body heat when you sleep. If you’re in a situation where it’s really cold, such as a mid-winter power outage, sleep in a hat to preserve additional warmth.

Don’t Be Afraid of Synthetics

Natural fabrics (those derived solely from plants, such as cotton, or animals, such as wool) are great, but their popularity sometimes gives synthetics a bad rap. When it comes to performance fabric, a little technology can be a good thing.

Manmade materials can offer the best elements of natural fibers without the downsides. For example, natural wool can be itchy and irritating. Some synthetic materials are made with a coat of silica applied to the fibers, allowing the fabric to mimic the water-absorbing properties of lanolin, an oil that occurs naturally in wool, without the itch-inducing burrs found in wool fibers.

While synthetics are currently enjoying the spotlight in the world of performance sportswear, they’re also bringing their benefits to sleepwear. In addition to keeping you warm and dry, they move with your body so you don’t have to deal with the annoyance of bunched-up fabric or twisted pants.

Can Natural Be High-Tech?

For the best of both worlds, some natural fibers perform just as well as their synthetic counterparts. Bamboo jersey, a fabric made from bamboo pulp, is lightweight, naturally moisture-wicking, and excellent at regulating body temperature. TENCEL is a fabric made from wood pulp and is super-soft. Both bamboo and TENCEL are biodegradable, which is a nice bonus for the eco-conscious consumer.

Can You Be Cozy and Sexy?

Some people want to feel attractive in their PJs, but cold-weather staples aren’t exactly known for their sex appeal. Luckily, lingerie and pajama manufacturers have caught on that there’s a market for sleepwear that’s both sexy and warm and now offer apparel like form-fitting flannel pajama sets in appealing prints.

Just not that into flannel? Silk pajama sets may be your new best friend. Silk feels great against the skin, it’s breathable, and it’s ideal for regulating body temperature. One caveat: real silk has to be dry-cleaned.

When shopping for cozy pajamas, just remember that overheating your body isn’t good for sleep. Your core temperature actually needs to drop by about one degree Celsius in order to initiate the sleep cycle, so if your pajamas are too hot, you’ll have a harder time falling and staying asleep. If you’re going to bed feeling snug as a bug but waking up sweating in the middle of the night, you may want to switch to sleepwear that traps less body heat.