Design fiction is an emergent field within HCI and interaction design, the understanding of which ultimately relies, so we argue, of an integrative account of poetics and design praxis. In this paper we give such an account. Initially, a precise definition of design fiction is given by drawing on the theory of possible worlds found within poetics. Further, we offer a method of practicing design fiction, which relies on the equal integration of literary practice with design practice. The use of this method is demonstrated by 4 design projects from a workshop set up in collaboration with a Danish author. All of this substantiates our notion of a poetics of practicing design fiction, and through our critical examination of related work we conclude on how our approach contribute to HCI and interaction design.