I liked the simple, sculptural shape of the book so much that I decided not the separate the folios or pages as I had initially supposed I might. It also didn't seem necessary; the eye fills in these sorts of details.
However, if you want to go ahead and suggest pages along the top bottom and side edges, remember that 'less is more'. You don't have to go too deep but you do need hard, sharp shadows.
Note:
This book project is part of a much bigger commission for Hay Castle, Powys, UK. You can see the whole, in 3 parts, on Woodcarving Workshops, of which this Open Book is the first part. The next part, adding an Ornamental etter H with a daffodil and bird to one 'page', you can now see here. In part 3 I carve an armorial device consisting of a heraldic Lion and Shield and you can watch it here.