A method includes: a severing step of successively producing a plurality of panels from a continuous web; an interval-increasing step of increasing an interval in width direction between a pair of panels, adjacent to each other in flow direction; a receiving step of receiving the panels by first and second rollers at first and second receiving positions, which are separated from each other in flow direction, wherein the first and second rollers for receiving the panels are placed so that axial lines of the first and second rollers are placed offset from each other in flow direction of the panels; and a placement step for placing the panels, from the rollers at first and second hand-over positions which are separated from each other in flow direction, onto opposite side portions of a body portion at the same position in the longitudinal direction of the body portion.