A conveyance method involves a conveyance control step of conveying a printing medium at least including a booklet along a conveyance surface; and a swing guide control step of rotating a swing guide before the printing medium passes a gap between the swing guide and a page turning roller until a first end of a flat section is above an arrangement surface of a conveyance surface and a second end of the flat section is below the arrangement surface of the conveyance surface, wherein the first end of the flat section is located further along the conveyance direction than the second end of the flat section.