I had this piece of raw canvas that I had stained as an experiment using acrylic paint and GAC 900. It was beautiful but It wasn’t a painting. I decided to treat it as fabric and sew a sketchbook wrap. I also repurposed some denim from a pair of old jeans. I love how the pocket from the jeans is perfect for an eraser and pencil sharpener.
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It has pockets on both sides large enough to hold a 8.5x5.5 Sketchbook and a small watercolour box. 
I tidied up the edges with seam binding. It has a button on the back and front to wrap the cord around for closing. I will make some tweaks in my next one.
Here is my first sketch in a concertina sketchbook I did during a walk at Rathrevor Beach. 
Let me know in the comments if you would like a step by step pattern to make your own sketchbook compendium.