A multiple-layout designation method rapidly and easily performs preparatory work for numeral control (NC) data preparation, in which one of contours displayed on a graphic display of an automatic programming device is manually selected as an NC data preparation object (S1), and the necessity of contour duplication is manually selected (S2). When the original contour is duplicated on the display by a processor of the programming device in response to manual setting of the name of a contour group consisting of the displayed contour and duplicated contours to be obtained by duplication (S3 and S4), or when the name of the displayed contour is manually set (S6), contour data for the contour or the contour group is generated. After setting of all the names of all the contour(s) or contour group(s) as NC data preparation objects, machining condition data associated with the contour name, or common to the original contour and the duplicated contour and serving as the machining condition data regarding the contour name, is manually set (S7 and S8). After setting of all the machining condition data, NC data employed for machining of each of the contour(s) and the contour group(s) are automatically prepared based on the contour data and the machining condition data concerned (S10).