I modified the corners so that the pages lay flat on the inside. The corners are very tight to put on so I used a small hammer to gently tap them on to the book. If they wiggle or fall off I place a tiny bit of superglue on the inside edge, enough to hold them on but are able to be pulled off if wanted.

I print this on it's edge and multiply it so that I have 4 in one print. I use a raft so the printer doesn't knock it over and when it's done I have a nice holder until I'm ready to put them on the books.