Sociological analysis of the graphical objects that order the environment generally focuses on the adjustments that are made to turn them into resources for action. Uses are thus seen as the driver of their performativity. Based on the case of subway signs, this article takes the opposite view and focuses on the activity of fitting out settings. The authors thus avoid both considering graphical artefacts as inanimate objects, and making immutability an intrinsic property of writing. They show, on the contrary, the crucial importance of maintenance work that, from day to day, maintains the spatial and material qualities of the objects and gives them a constantly updated performative force.