“Profile work,” that is strategic self-presentation in social network sites, is configured by both the technical affordances and related social norms. In this article, we address technical and social psychological aspects that underlie acts of sharing by analyzing the social in relation to the technical. Our analysis is based on two complementary sets of qualitative data gleaned from in situ experiences of Finnish youth and young adults within the sharing mechanisms of Facebook and Last.fm. In our analysis, we identified social norms that were formed around the prevailing sharing practices in the two sites and compared them in relation to the sharing mechanisms. The analysis revealed that automated and manual sharing were sanctioned differently. We conclude that although the social norms that guide content sharing differed between the two contexts, there was an identical sociocultural goal in profile work: presentation of authenticity.