I've finally written up the pattern for my World of Warcraft banner. It can be found as a free download in my Ravelry store. download now
I tried to explain the dowel rod assembly as best I could. To hang the dowel rods I would probably use something like these command hooks. They are inexpensive and should easily hold the banner up.
If you have any problems, please don't hesitate to ask and let me know so I can try to clarify.