It depends on “what” you are interested in from his thought, as his texts are vast. I read “Man and his symbols” first and then “Archetypes and the collective unconscious” - I think these are frequently considered a good intro as they are the most quoted from his. “Psychology and Alchemy” is really interesting but more dense. “The red book” is quite impressive but a completely different animal.
As far as editions go I cannot say much as I read Spanish editions mainly (recently a Spanish publisher edited his whole works and it spans more than twelve volumes with up to 600 pages each, so you get the idea of why I said his body of work is vast).
Also, something I encountered when reading him is that I felt he wasn’t too good of a writer, so it sometimes got difficult for me to get what he means, especially when some concepts are all of his own. So reading others’ research about the specific texts you read can be very handy, imo
Other than that, don’t feel like you have to read a whole book - some of the reads I have liked the most from him were short chapters or articles within the “complete works” books, I’d be down to discuss specific essays/chapters that I liked but some I don’t know if they are available in English or under which form - Edit: if anyone reads in Spanish, the publisher is Trotta.
