A method for releasably connecting a fitted device (200) to a piece of furniture (320) uses a connecting device (110). The fitted device (200) includes an attachment element (220) disposed on its housing (5), and the connecting device (110) includes an at least two-part connecting element (14) and a mounting gauge (130). The method involves inserting the fitted device (200) into an installation recess (310) adjacent to the piece of furniture; aligning the fitted device (200) relative to the piece of furniture (320); positioning the mounting gauge (130) on the attachment element (220); connecting, guided by the mounting gauge (130), a first part (122) of the connecting element (14) to the piece of furniture; removing the mounting gauge (130); and fixing the fitted device (200) on the piece of furniture (320) by connecting a second part (125) of the connecting element (14) to the first part.