Thanks!
I wrote 550 of them myself and relied on submissions for the rest.
My procedure was to bring up lists of the actual Appendix N titles, multiple thesaurus’s, lists of mythological places, figures, and things. Then puzzle over all of that to come up with titles. I also tried to keep in mind that the title should be able to be interpreted in multiple ways to give the writers flexibility.
Also I had to envision it on a 70s book cover lol