In this extract from her April 2020 article in The Artist, Deborah Walker explains how to make a simple concertina sketchbook from a single sheet of paper.
How to Make a Concertina Sketchbook with Deborah Walker
A sheet of good-quality cartridge paper, A2 or larger
A craft knife or scissors
Paper creaser or bone folder
Make Concertina Sketchbook
Fold the paper in half lengthways and then fold each end to the middle. Firm each crease with the bone folder.
Open it out and flatten it. Fold the paper in half in the opposite direction, then each half to the middle, firming the creases
Open it out to give 16 pages
Cut from the right side, stopping at the first left fold of the first row. Then cut from the left side, stopping at the last fold on the middle row, then repeat the first cut from the right side to the first fold on the last row
Starting at one end, fold into a concertina, reversing folds as you go