Up until 4 weeks ago when York University went on strike, I had been taking a class called "career development for musicians." It focused on the brass tacks of how to make a living making music, including spotlights on different careers, getting connected, how to get paid, how to write grants, etc.
I'm the oldest guy in the clas, and at some point one of my classmates asked presenter John Switzer, the Program Coordinator for Seneca's School of Communication Arts, about how to get work playing as a sideman. Mr. Switzer, having asked each of us for a brief synopsis of our music careers, deferred to me. I think I said something about "working your way up the (musical) ladder," but really that's a pretty vague statement.
Ever since then, though, I've been mulling this question over, and regularly coming up with new things to say on the subject. Now I'm by no means a paragon on this one, but I nonethless do have what i think is valuable insight.