What Diana calls a circle journal, I know as a maze book but whatever the name, the concept is the same: a multi-spread book made from a single sheet of paper. Decorate, fold, cut, fold, and then decorate some more. This book structure also includes a pocket where one can store an additional page but my book did not take advantage of that feature.
It took me a long time to finish this class because I couldn't come up with a theme for my circle journal but finally it hit me: I wanted to do a little artist book about my personal lexicon.
A lexicon is a set of symbols or images that appears regularly in an artist's work. The artist may or may not be aware of the existence of their personal lexicon but if not, it is easy to discover. Search through past work and see what symbols repeatedly make an appearance.