AMA: Privy Vice President of Marketing, Daniel J. Murphy on Establishing Product Marketing

I'm curious if you've observed the impact of adding a PMM to smaller organizations or if you think they're most impactful in larger organizations?

I'm on my 5th year of product marketing in my career, with another 5 years before that in general demand gen at very small companies. I've had management experience in the past, but not in a Product Marketing role. Often times in smaller companies, there will be 1 or 2 PMMs, usually in a very flat hierarchy, or a single boss, with no room to really move up a proverbial ladder and into management experience. So what are ways that I can prepare myself now, so that if the time comes to apply for a Director position (either internally or at another company) that I can be considered even without recent people management experience? Are there any courses for this that are highly regarded in the management arena?