Next to mountain folds and valley folds, squash folds are the most commonly used folds in beginner level projects. A squash fold gets its name from the fact that you're basically squashing the paper into the desired shape.

To make a squash fold, you need to open the paper slightly before pressing it flat into the desired shape.

The squash fold can be seen in this easy origami envelope project

I recommend using 12 x 12 scrapbook paper instead of traditional origami paper for this design so you will have an envelope big enough to use to mail a handmade greeting card. You can use regular origami paper if you wish, but your envelope will be quite small when folded.

To make an origami envelope:

1. Fold your paper in half diagonally to make a triangle. Fold the top layer down.
2. Fold the right side 1/3 of the way across the diagonal fold.
3. Fold the left side over so that the left point meets the right edge of the paper. Fold the left tip back so it touches the left corner. This will make a small triangular flap.
4. Separate the triangular flap. Make a squash fold to transform the flap into a flat diamond. Tuck the top part of the envelope into this diamond to secure it. If you're sending your envelope through the post office, I would recommend adding a decorative sticker of some sort over the closure to make sure it doesn't come undone before reaching its destination.