In light of studies on informal language teaching (SENEFONTE, 2018) and drawing on Socio-Discursive Interactionism (BRONCKART, 1999), this research aims at presenting a didactic proposal involving a sequence of systematized activities that address informal English through the sitcom genre. Therefore, this study belongs to the area of Applied Sociolinguistics and the field of language teaching/learning and teacher education. The first episode of the show How I met your mother forms the basis for the development of the exercises, which encompass current trends in language teaching and learning. The literature review conducted in this paper reveals the scarcity of studies on the teaching of informal English through sitcoms or any other audiovisual genre, suffice it to prove relevant the debate on this theme. To sum up, this paper is expected to expand the literature on this topic and enable teachers to reflect over their practices concerning language variations.