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.