Home is a person’s castle, a private and protected space. Internet-connected devices such as locks, cameras, and speakers might make a home “smarter” but also raise privacy issues because these devices may constantly and inconspicuously collect, infer or even share information about people in the home. To explore user-centered privacy designs for smart homes, we conducted a co-design study in which we worked closely with diverse groups of participants in creating new designs. This study helps fill the gap in the literature between studying users’ privacy concerns and designing privacy tools only by experts. Our participants’ privacy designs often relied on simple strategies, such as data localization, disconnection from the Internet, and a private mode. From these designs, we identified six key design factors: data transparency and control, security, safety, usability and user experience, system intelligence, and system modality. We discuss how these factors can guide design for smart home privacy.