The invention relates to a method and device for installing an elevator in an elevator shaft, having the following steps: i) arranging a model in the elevator shaft, so that the arranged model represents nominal dimensions of an outline of the elevator; ii) arranging at least one light source at a nominal position of the model, so that the light source is directed in a provided travel direction of the elevator; iii) projecting a light beam starting from the light source, wherein the light beam defines the nominal position along the provided travel direction in the elevator shaft; and iv) using information about at least one location of at least one projection point of the light beam in the elevator shaft for installing the elevator.