This is 'The Complete Shithead's Guide to Superhero Costumes' as seen in 'Superhero Movie'. Just after Xavier's wife tells Rick to 'Make a costume, shithead!', he's seen in his room drawing up ideas for costumes. You only see a corner of one of the mock-up pages in the movie itself, but the cover can be seen in a deleted scene on the DVD and Blu-ray. The book is a real 'Dummy's Guide' book with the cover torn off and this printed cover glued back on. There are two pages of superhero costume information glued inside the middle of the book. It's one of these pages that you see on-screen.The first screen shot here shows the corner of the book and one of the mock-up superhero costume pages. The second image is from the deleted scene showing Rick Riker holding the book up so you can see the cover. The small image is a picture of the whole page you see on screen (page # 147).
