I can only speak to my experience, but I got lucky that “CSM” really started evolving as a role around me and I was basically already doing it, so it was an easy transition. That said, you’d need to go back to a customer facing role. I know there are Associate CSM roles now which I think is basically an entry-level csm role. It might be easier for you to start talking to people within the company you are currently at. If they know your experience and skills, it would be easier to go for a role change from training to csm. Once you have that first CSM role under your belt and on your resume, you’re in. Then just work your ways up the levels of csm.
I’m always weary when I get pocket pairs