Step 1: Get Your Books
You'll need five or six hardcover books that you're willing to ruin. Make sure they don't look out of place on your shelves. A dictionary will be obvious on a bookshelf full of comics. Avoid shiny type on the spines.
Step 2: Remove All the Pages From Your Books.
Open the book. There's a page glued to the inside if the hardcover. Connected to it is a page that's a part of the book. Use a razor to cut as close to the binding as possible between those two pages.
Do this for the back cover.
Now you should be able to start pulling the pages away from the binding. There should be a little resistance, but not much. If it's particularly difficult, put water in a dropper and drop in into the crevice.
Step 3: Remove the Spines
Your going to want to cut the spines off the covers. You want to cut on the soft spot right wen the cover ends. All you need is what you would see if the books were on the shelf.
Do this for all but 2 books.
Decide which book you want at the front and which at the back. You want these two books to be about the same length.
For the front book, just cut off the back cover.
For the back book, remove the front cover.
Step 4: Put It All Together
Line up the spines in the order you wan them. Make use the bottoms make a straight line and nothing is slanted. Then, use double-sided tape to secure it all together.
Cut a piece of poster board to just below the width of all your books. Use the other side of the tape to stick it on
Step 5: Add Some Stability
Now you have the basic look down, it put this on your bookshelf and it will be crushed. Take a piece of cardboard or like substance (I used balsa wood because we had it lying around) and cut it to the size of the spines.
Hot glue this on and weigh it down while it dries.
Step 6: That's All There Is!
Put your new hideout on your shelves above eye level. You don't want people to be able to look down and see that it's fake!