Step 1: Folding and cutting
Step 2: Making the holes
Use one inner sheet with four holes as a template to finish the other sets. You will get aligned holes.
Step 3: Sewing
Step 4: Gluing
Find a regular piece of cloth, from a discarded shirt for example. It should cover the back of the sections and extend around 1.5cm (0.6in) around the first and last page (Please see last photo of the set).
Apply adhesive to the back of the sets and half an inch on the first and last page of the notebook, then attach the piece of cloth. Finally make sure the piece is glued to the sheet and trim any excess.