After watching the video by Adam Savage, I used sheets of butchers paper to draw a template of a figure my size so that I could plan the size of the cane rings I would need for my Totoro.
This process took most of the afternoon to work through, but I ended up with 16 ring dimensions. The widest ring is 1m in diameter, which means that the circumference of cane is 3.2 m!
Now that I have a plan, it is time to order the cane. I am ordering the cane from http://www.wickerworks.com.au/. I decided to order a 500 gram bundle of 5mm round core cane which will give me about 50 metres of cane to work with.