Jennifer Garner, InStyle's October cover girl, is many things: an actress (up next is Disney’s adaptation of the children’s book, Alexander and the Terrible, Horrible, No Good, Very Bad Day, in theaters October 10); an activist (along with Halle Berry, she successfully campaigned Congress for an anti-paparazzi bill); and—her most treasured role—a mom (to daughters Violet, 8, and Seraphina, 5, as well as son Samuel, 2, with husband of nine years Ben Affleck).

She is also impeccably gorgeous in the pages of the October issue, available on newsstands and for digital download September 19. Swathed in rich textures and layers by Burberry Prorsum, Stella McCartney, and Michael Kors, Garner was perched atop a cliff in Big Sur, Calif., a location that's one of the 42-year-old's favorite places because "it's dramatic, and foggy, and moody...and here you can really convince yourself that it's fall."

For more from Garner, like her favorite look from the day, the "depressing" secret to her workout routine, and what's inside her makeup bag, watch the video above, and for the full interview and photos pick up the October issue of InStyle, on newsstands and available for digital download Sept. 19