Step 1: Visit your favorite Home Improvement Warehouse
Step 2: Gather Pieces
Ten - 2" 90 degree Street Elbow - spiral
One - 3" to 2" reducer - Bell
Its a short shopping list... and its all you'll really need to get started!
In these pictures, I'm assembling it in the aisle at Home Depot... Starting with the mouthpiece, I attach the first elbow... with each added section, you want a slight 'twist' or offset to make a proper spiral. Unless, of course, you don't want to make a spiral... But I'm making a spiral. So here we go.
Step 3: Final Assembly
A year or so ago, I made a video with the black Spiro-Didge, showcasing my fantastic skill... *note massive sarcasm in preceding statement*
Spiro-Didge video on MySpaceTV