Start with what's underneath — a fitted long-sleeve top, bodysuit or thermal base layer under a dress adds warmth without bulk. On top, an oversized knit worn over a fitted mini or midi is one of the easiest and most popular winter dress combinations. A tailored blazer or structured coat works well for a more polished look. For footwear, ankle boots or knee-high boots naturally fill the gap between the hem and the ground, which helps with warmth and ties the layered look together. Keep the layers fitted close to the body and save the volume for the outer layer.