MATERIALS:
Book/Notebook*
Xacto Knife/Box Cutter
Ruler
Elmer's glue
OPTIONAL:
Felt**
Super glue
*Make sure the book is wide and thick enough to fit your tablet comfortably; mine was a little on the thin side.
**If you're going to make this, I would strongly recommend lining it with felt--if you do, make sure to account for the thickness of the felt when cutting away at the pages.
If you have appropriate woodshop tools lying around, I would just remove all the pages entirely, and fashion a wooden frame to fit inside; otherwise, follows these steps:
1. Measure the length and width of your tablet, and mark the locations of your tablet's buttons (volume, power, etc). Trace this onto the first page you will cut.
2. To hold everything in place, spread a THIN layer of Elmer's glue over the pages. If you add too much, the pages will wrinkle. Periodically re-apply glue as needed.
3. Fold book flaps back, and start using the box cutter on the pages; at some point, check to see if the case fits. If you have rotary scissors on hand, they'll make life so much easier.
4. Trim away areas for button access. Secure with glue as needed.
5. Line with felt; cut appropriately around button access cutouts. Snip squares off in the corners so the edges fit together. Use superglue to attach the felt to the inside of the pages.
6. Trim anything unsightly, re-glue pages, etc. Admire your new case!
(pardon the watermarks--it was either these images or the raw 5000px file)
It'll never compare to say, a Dodocase or Portenzo, but if you're broke or into customizing your own things, give it a try.
See more pics here: DIY: Book to Tablet/E-Reader Case | Tights and Tea