This also makes a good present. A friend of mine said she always wanted to make/have a hollow book, so she could put random stuff in there. One day I stumbled upon the idea again, and decided I'd do it. I'm giving it to her for her birthday and putting her favorite candy (M&Ms) and a note in it.
First, set aside the first couple pages you'd like to keep uncut, plus one. If you don't want any pages uncut, just leave one for a step in the future.
Set aside the pages you've picked. I taped mine to the cover of the book. Then cover it in plastic so the glue won't get on the inside cover.
Now, before you glue, measure out a 1/2 inch border around the page & draw it out.
Once completely dry, open book to your framed page. This is when you start using your box cutter/X acto knife and your ruler. Take your ruler and line it up with the lines you drew. Take your box cutter and cut out the rectangle you drew. Keep doing to that to ALL the pages, until you hit the end. This will take a VERY LONG TIME, so I suggest some music or something of the sorts to keep you going through the whole time.