A little Background

There are many methods to create and fold origami. Many people choose to doodle, accidentally coming upon models. John Montroll and J.C. Nolan are two that come to mind as people that are able to doodle very well. Akira Yoshizawa is a creator who uses much feeling and artistic taste in his models, making them hard to diagram exactly and hard to fold exactly. Yoshizawa's models have much expression and life in them that only few can repeat. Others, such as Robert Lang, Satoshi Kamiya, Peter Engel, Jun Maekawa, and Hojyo Takeshi create many modes from a topological method. This method is a favorite of mine, because it is more technical and scientific. This method involves mapping out on the flat piece of paper the locations and sizes of each appendage of the model. Once this is mapped out, there is a repeatable algorithm that allows one to map out the location of the major creases that will produce a base with the mapped out appendages. The creator often maps out the creases before folding anything, and this allows them to create a basic base in very little time. Often this method produces some of the most complex models possible, but the downside is that often the models lack the life and inspiration in models designed in other ways. Topological design stems from the math of topology, where one learns how to morph one shape into another. Namely a flat sheet into a 3D form. Once this mapping is complete, the creator can figure out how to diagram a temporal instruction for folding the model, or may simply publish the mapping and allow the folder to figure out how to fold the model. This mapping of the crease locations for the base of the model is called the crease pattern.

Introduction

The crease pattern normally shows only the locations of the creases on the flat sheet of paper. This means that the folder must determine the direction of the creases (mountain or valley), how to collapse the crease pattern so that all the creases shown exist in the collapsed base, and must figure out how to finish and shape the model to it's final form. Three different steps thus arise for me,
1) Figuring out direction of the creases (or at least as many as you can figure out),
2) Figuring out how to collapse the crease pattern into it's base,
3) Figuring out how to turn the base into the finished model.
Step 3 Often is based on photos of the finished model, where the folder has to attempt to use well-known methods to shape the model into something as similar to the photo as possible. This is not exact, and often I am unable to reproduce exactly what is photographed. For collapsing the base, one must often figure out what major locations on the crease pattern correspond to what appendages and locations on the final model. This mapping of appendage to location on the crease pattern helps to collapse the model, and determine directions of the creases.

Please choose the tutorials on the left for interactive descriptions of how you can begin learning how to fold from crease patterns. I suggest beginning with the beginner ones even if you are experienced in crease patterns.