Kristin Cavallari was back in a two-piece yesterday for a photo shoot in Malibu. The starlet seems to be at home in her swimsuit these days, as there was also a Kristen Cavallari bikini sighting Tuesday at her friend's place. She managed to fit in an evening at the spa before reporting to the set, but Kristin had enough free time between snaps to tend to her Twitter account. Kristin traded tweets with her makeup artist Carlene, who she thanked for making her "look purdy." The tables were turned, too, as Carlene shared an image of Kristin showing her skills with the brushes and eye shadows.