Obviously learn what you need to learn. However I'd spend time now building up a social media following and learning marketing.
I've lost count of how many personal trainer buddies I've had over the years who got qualified and never got hired or lasted more than a year as a PT.
Meanwhile there are lots of guys out there without the qualifications who kill it because they clearly know what they're on about, have the results to prove it, that do well because they know how to market themselves.