This article is focused on the production and design of the self by upper-secondary school students in Mexico from the standpoint of the practice of taking a selfie. Based on the observation of "Instagram" profiles, interviews, and a survey, I investigate the place that selfies have in the design and self-presentation of young people, paying particular attention to the epistemic practices they mobilize and the operations they carry out with social networks. The design and presentation of the self is based mainly on editing and appears as a constant exposition validated by others; this process shows that subjects are self-designed while they are a result of the design imposed by the social media platforms, so this design of the self does not call into question the hegemonic canons and hierarchies.