How to make a Sonobe Unit
Modular origami models are a joy to make! No glue. Sturdy. All you need are square sheets of colored paper.
Want to make your first modular origami model? The simplest building block for such models is the traditional Sonobe Unit! The unit is quite easy to make.
Step 1: Familiarize yourself with Origami symbols like mountain and valley folds. That will help you understand instructions like these (Sonobe unit variations) comfortably.
Step 2: Build your first 'traditional Sonobe Unit'. The best instrutions are available at WikiHow: Make a Sonobe Unit.
You may also want to see Photo Instructions (step by step) or Photo Instructions (step by step).
Step 3: Repeat Step 2 to make multiple traditional Sonobe Units, depending upon what model you would like to assemble. A good starting point is the Cube (6 units). As you gain confidence, you may assemble other models like Toshie's Jewel (3 units), Large Cube (12 units), Octahedron (12 units), Ocosahedron (30 units), Spiked Pentakis Dodecahedron (60 units) and Dodecahedron (90 units).
Step 4: Crease each traditional Sonobe Unit according to the model you are building. The crease patterns are described precisely here and here (free Chapter from Meenakshi Mukerji's first ever book on modular origami).
Step 5: Assemble the traditional Sonobe Units together. Assembly instructions are available here, here (free Chapter from Meenakshi Mukerji's first ever book on modular origami) and here. If you find these diagrams hard to understand, watch videos and step-by-step photo instructions listed below.