Okay I bought this ring about 9 years ago at the Northern CA Ren. Faire (woo) The other day the girls were in my jewelry box & they took it apart. I could not for the world get it back together until I found this tutorial online by the maker.
First things first: This only works for Grenne brand puzzle rings. On one of the 4 bands you'll find the engraving. Hold that one up, all the others should be dangling down (curvy parts downward)
Take the bottom ring and bring it upward to the top ring (it should look like you're closing a book). Twist that ring until it locks with your top one (making the middle two stuck inside a figure 8)
Rotate the other two dangling rings into the figure 8
***DO NOT FORCE YOUR RINGS!!! THIS WILL DAMAGE THEM!******