For many paper folding projects, you need to start with a square piece of paper with four equal sides. Most of the paper you have laying around, however, is probably rectangular. Luckily, there are two easy ways to turn a rectangle into a
Craftside: Origami Envelope from 8 1/2 by 11 paper
How to Make a Square from Rectangular Paper
How to Make a Square from Rectangular Paper: 8 Steps
How to Cut a Square from a Rectangle, Origami Basics
Make a Rectangle Paper to a Square Paper : 5 Steps - Instructables
DIY Easy Paper Crafts: How to Make Origami Rectangular and Square Box by One Diagram Tutorial
8 Tips for Printing Inkjet Greeting Cards
Little Artists: Origami Boat - Niantic Children's Museum
Useful Modular Origami Display Frame Tutorial - Paper Kawaii