People use social media platforms such as Facebook, Instagram, and LinkedIn for impression management (i.e., self-presentation). They use social media to present information about themselves intended to curate a particular image, for example, by posting work accomplishments on LinkedIn or vacation photos on Instagram. As self-presentation on social media becomes increasingly complex and time-consuming to manage, it is important for researchers to better understand what drives selfpresentation behaviours across platforms. Drawing from the focus theory of normative conduct, we introduce the self-presentation affordance-norms-behaviour framework to examine normative selfpresentation behaviours across social media platforms. Specifically, we outline a qualitative study utilizing both interviews and netnography to examine how social media affordances for selfpresentation may activate different personal or social norms for self-presentation, which guide the self-presentation behaviours users employ on different social media platforms. Our study promises to improve researchers’ understanding of how norms differ across social media platforms and how selfpresentation affordances drive self-presentation behaviour through the norms the affordances activate. Such knowledge is important for better informing design and use of social media platforms and can provide insight into self-presentation behaviours that could help stymie negative consequences of social media such as cyberbullying and addiction.