Draw a storyboard for your animated sequence, using rough paper as a trial run before you create the book itself. Flip books usually tell a simple story--somebody falling down or kicking a ball--so work out the sequence of events and decide what images you need to use, and how many images you will include in the book. It's hard to flip a large amount of pages--about 30 images is usually sufficient.
Draw the final pictures for the book. If you use small square sheets of paper, the drawings can go in the middle of the page. If you decide to use larger paper sheets, it is best to draw your pictures in the top or bottom right corner of the page, so that the viewer can see them easily while he flips the pages.
Staple or stitch the pages of your book together in the correct order. Make sure the pages cannot come loose--your animation needs to be viewed in sequence, and if a page falls out, the effect will be compromised. Another option, if you are using thicker paper, or photographic paper, is to clamp and drill two holes through the pages of your book, and hold them together with nuts and screws.