So, here's what I have done so far. It still needs some more work, but not much. Then the hard part will be collecting all the birthdays and writing them in the little folders on each page!
This is the front, obviously:
And a view from the top:
A sample of the inside pages:
I used ribbons instead of the posts that came with it and punched an extra hole in the center to make it more secure. I really like it a lot, it's turning out much better than I expected. Can't wait to finish it though, it's been a lot of work!