I work in a very corporate environment with dudes in suits and such.. and just can't openly walk around with an army book without feeling out of place, so recently, I decided to cover some books. You all may have forgotten this technique since you are long out of grade school, but I have kids that need books covered all the time. This is also efective if you just want to protect that new $50+ book.
I have started with a FedEx pack that is larger than my book.. and cut it open so it folds like a book.. fold the top an bottom edges to the height of the book. The cover material works best if it is significantly bigger than the book, This fedex pack is a little small to reliably stay on.

Tuck one side in and tape it to itself, not to the book.. close the book to see where the fold should be on the other side, insert and tape it.
Here are two army books I have covered with crap from my work mail room..
