In the olden days (pre-CS5), I’d build a book cover in one page, based on the dimensions of the front and back covers, plus the width of the spine. That approach was fine — unless the spine width changed. But now, using the spiffy new Multiple Page Size feature in InDesign CS5, it’s much easier to deal with changing spines. Here’s how:
1. First, you have to be able to glom the pages together. Create a three-page document. Then, in the Pages Panel menu, UNcheck “Allow Document Pages to Shuffle.” At one time, this read “Keep Spread Together,” but that made too much sense. Essentially, InDesign insists on maintaining spreads: If a page is deleted from a multi-page spread, the following page “shuffles” up to fill the void. Unchecking the Shuffle option stifles this behavior, so you can stitch pages together and pull them apart as you wish.
2. Drag Page 2 up and glue it to Page 1 (below).
3. Select the Page Tool, and click on Page 2. In the Control Panel, use the Transform Proxy to anchor the left side of the page, then change the width of the page in the Width field in the Control Panel.
4. Drag Page 3 up and glue it to the right side of the spine. Place all your artwork and text, and you’re done (or so you think).
5. At about this time, in the Real World, your boss would call in a panic and tell you that the verbose author has submitted another chapter — you’ll have to change the width of the spine. While you’ll have to massage the artwork, changing the spine width is painless. Just select the spine page with the Page Tool, and enter the new width in the Control Panel. This will result in the spine either overlapping the front cover (p. 3), or leaving a gap between the spine and cover. But that’s easily rectified — just use the Page Tool to reposition the cover page, and you’re done.