A predetermined area of a print surface is captured by a camera as a plurality of subdivided images to include an end edge portion of a previously printed image on a coating-target object, the end edge portion serving as a connection portion with an image to be drawn to be printed contiguous to the printed image, a composite print surface, which is a plane projection of the print-target surface which is non-plane, is created on the basis of the captured subdivided images, an edited image to be drawn is created by superimposing the image to be drawn on the composite print surface, and the image to be drawn is adjacently printed contiguous to the printed image on the basis of the edited image to be drawn.