Start the season off right by stocking your closet with fall's must-have denim styles. 1. The flare: This ultra-flattering, leg-lengthening style is a must for boho babes. 2. Distressed skinnies: Add some edge to your look with distressed details. 3. The girlfriend: Keep it casual cool in this relaxed silhouette. 4.The barely boot: One of the most universally flattering jeans ever.