These instructions show how to fold a sheet of rectangular paper into 16 even panels. Some terminology about folding:
 Mountain Fold |
 Valley fold |
 A bone folder will help you make clean, crisp creases. It’s a dull edged hand tool that is made of animal bone or teflon. Holding the tool flat, run the pointed edge along a crease to make it crisp. |
Start by folding the paper in half, short end to short end and, using your bone folder, make the crease crisp. This is your reference fold, and it is always the fold in the middle of the sheet. Using the reference fold to make subsequent folds ensures your accordion will have evenly sized panels.
Fold A to the reference fold and crisp it up with your bone folder (figure 2). Turn the paper over and fold B to the reference fold, again crisping up the fold.
Open up the paper to its full length, reverse the reference fold (fold it in the opposite direction, so all the folds are mountain folds) and fold the paper in half again.
Grasp fold A and fold it to the reference fold, then fold the end of the paper (at B) to the reference fold. Bone everything down. Turn the paper over and repeat on the other side.
Be sure to use your bone folder to press on the edges to make them crisp.
Unfold the entire sheet and you’ll have 8 sections. Reverse all the valley folds to mountain folds, as shown below.
Fold the sheet in half one last time, at the reference fold. Grasp the fold closest to the reference fold (A) and fold it on top of the reference fold.
Continue folding each mountain fold to the reference fold, working right to left.
Turn the sheet over and, working right to left, fold the mountain folds to the reference fold. Open the sheet and you’ll have 16 panels.
