If there's one thing missing from my wardrobe this season, it's a plaid scarf. Charming, festive, attention-grabbing accessories, the plaid or tartan scarf is a must-have. How to wear it? Pick one color from the mix and use that as your grounding piece. As seen here in the $29.99 "Plaid Blanket Scarf," (upper right), blue might be the hue you grab onto. Choose a dark or medium blue blazer, a white blouse, a burgundy hat, and blue jeans, of course, to complete the look. Do the same with any other plaid or tartan. Seen here are four of my favorites this season.