Abstract: A method for applying a position marking for a working position to a substrate, for example a wall, a ceiling, a floor or the like, at a marking position assigned to it, comprising: a. unsystematically or systematically moving a portable marking system over a marking area of the substrate; b. determining at least one position of the marking system; c. marking at the determined position of the marking system, provided that the determined position coincides with the marking position or at least coincides with the marking position to a predefined or predefinable degree of accuracy. The invention also relates to a marking system.