Two methods: 1 for page alignment, width: 185+ spine /2, height: 260, and bleeding on four sides of 3 mm 2 Make a single page, width: 185+ spine+185, height: 260, bleeding on all sides. The margin is not important, as long as it is not too far from the edge and will not be cut off. The key is to conform to aesthetics. If there is bleeding, remember to bleed.

Either way, draw two vertical lines on the page to represent the spine line, which is convenient for the printing house to use. The positions are: X= 185, and the other X= 185+ ridge line. These two lines will be displayed on the page, and a white frame with the same size as the page will be made to cover the spine line on the page, so that the spine line will only be displayed outside the page.