This is a link that explains it better.
Basically it's a book, where every page has a different thing on it, and you do it, and it totally makes a mess, but it turns the book, into your own - by 'wrecking' it. ^_^
This is how fat mine is - as of yesterday (all the post its are pages that still are blank and need to be done - I do have a LOT of half finished pages but those didn't warrant post its... yet. :P):
It's awesome fun! :D I love mine! ^_^ I've only had mine for like a month now. :) Totally recommend getting one, anyone can do it! :D
Thanks!! :D I'm trying to add as much color to mine as I can! :P