Have your books started to grow in a uncontrollably fast pace that result's in them not having a place to live in? like the books on the picture above? Yeah I have the same problem, and Im going to help you solve it.
First thing first, If your bookshelves are OVERLOADED with books it's probably time to bye a new bookshelf. You can find bookshelves for a cheap price, I bought mine for $45 which I think was a good price, but I saw even cheaper ones at the store (IKEA)
Take down all your books and lay them on the bed or some place where they can just lay and chill.
Write down on a paper how you wan't to organize your books. I always reorganize my books, right now I have my books in color-coordination starting with the the colorful books. I used to have my shelves sorted with the paperbacks separately and pocket books separately.
This step is all about personal preference.
Start shelving them up, It's easiest working from the top down. A tip is to keep the books you like the most in the middle so that they are easier to reach.
DO NOT fill the big empty spaces with other stuff because when new books are coming in you wont know where to put the decorations you used to have on your shelves. I used to have my perfume bottles on the space my books didn't take up. bad idea.
Admire the view of your new bookshelf
~stay smart, stay chic