Creating the spine for a perfect bound document

Create a 3 page spread with the middle page 4.233 mm wide (minimum page size in InDesign)and set up bleeds according to your needs. To be able to resize page to the smallest size, the document margins and gutter have to be minimal too. Create a text frame of the same width as the middle spine page. Create anchored frame of the size sufficient for the entire spread and bleed in the text frame. This will ensure that the wrap around graphics is centered on the spine