When temperatures plunge, many folks reach for their heaviest winter jacket before heading outside. But what’s underneath can be even more important in keeping you warm and safe. “Layering is the way we dress to make sure our body is comfortable when it’s cold out,” said Claire Wilson, executive director of The Loppet Foundation, a non-profit that promotes winter recreation in Minneapolis. “Typically, you’re gonna go outside and be a little active, so you’re going to walk to the bus stop or maybe try cross-country skiing or snowshoeing, you’re going to work up a little bit of a sweat if you have on your warmest winter jacket,” Wilson said. “And then the second you stop you’re going to get really cold really fast.” Wilson recommends thinking of layers in three levels: a base layer that wicks moisture away from the body, a middle layer to provide extra insulation around your core, and an outer shell to protect against wind and the elements. Wilson says thrift stores or even your closet can be great places to begin building your winter wardrobe. Polyester and wool blends work better than cotton close to your skin, which retains more moisture. A warm hat, gloves and wool socks complete the ensemble.