A process of pressing a blank to form an intermediate formed component configured including a top plate, the ridge lines at short direction ends of the top plate, and vertical walls facing each other in a state extending from the respective ridge lines and at least one of the vertical walls configuring a curved wall curving as viewed from an upper side of the top plate, such that a step projecting toward an opposite side to a side on which the vertical walls face each other is formed to the curved wall so as to run along a length direction of the top plate. The method includes pressing the intermediate formed component to narrow a projection width of the step, or to move a portion of the curved wall where the vertical walls face each other.