It's time for fall for Sienna Miller! The actress just released the fall 2011 lookbook for her label Tweny8Twelve—the collection she co-designs with sister Savannah Miller—and she models a few looks from the new lineup for the photos. Inspired by the '60s, the autumn offering features soft chiffon skirts, cozy sweaters, printed silk shorts, and more items you can mix, match, and layer. Select pieces from the Twenty8Twelve collection are already on sale at Shopbop.com and Nordstrom.com, and more will hit stores and online this month. See Sienna Miller model some of her new pieces in the gallery.