I did not cut out the panels on the outside edge. Instead, I cut in the middle between the two panels. After making the 3 quilt sandwiches, I sewed the pieces together making sure to leave an opening for turning. Before turning, I trimmed the excess fabric and batting with my rotary cutter and mat. I also cut the corners off to reduce the fabric that would bunch up when turned.
Once the fabric was turned, I pressed each piece to flatten the seams. I also pressed the seams of the opening inward to make it easier to sew. Using an invisible slip stitch, I hand sewed the openings closed then pressed the seams again.
Lining up the 3 "pages" was a little challenging since they weren't exactly the same size (I am certain this was due to the panel printing, not my sewing skills). Once the binding was sewn the only thing left to do was to write my niece's name on the back cover.
The book is really cute and I think my niece will enjoy chewing on it.