Several answers are offered in comments to a post on this topic at the Book Design Review. Many people suggest the “traditional” route of design school. The Book Designer offers some good advice (if not the tightest sentence grammatically), saying “barge into as many cafes, design conferences and publishing houses with your portfolio till you meet the right person.”
I didn’t notice anyone speaking up who had followed my route. I started on the editorial side, got into a little design for some folks I knew, meanwhile working my way up to director and editor-in-chief of a publishing company, until I reached the point were I could assign myself design jobs when I wanted to. Now I design museum art books (or assign them to free-lancers if I prefer). Why isn’t crossover between design and editorial more common?
I hope not to sound complacent, since I know this career stuff is hard and doesn’t necessarily work out quite the way one might like, but at the same time it is often the case that if you resist selling out, are persistent, and pursue what interests you, then when a break happens you will be positioned to take advantage of it. Of course, you always have to keep improving your skills. You have to pay your dues.
Anyway, it’s good to do different things, changing course from time to time. Otherwise your brain gets lazy working the ruts of habit, and you stop growing in a creative way — I say that wondering whether I might be treading some ruts myself these days. It could be time to shake things up …