The outer ring is held in place by pushing the pot up against a stone or log...and when not it use, it can also serve as a seat cushion or pillow.
And no, I don't have plans. If you need them, this project is not for you!
Check our our website: http://www.backpackthesierra.com/
Or just read a good mystery novel set in the Sierra; https://www.amazon.com/Danger-Falling-Rocks-Paul-Wagner/dp/0984884963