In my above post I meant to say it WONT be easy....
Anyway, starting where you are with someone you know is a great place to start. The key thing is whether you are looking to get into baseball strictly as a trainer or as a coach as well. Tons of guys who got drafted or played college ball teach hitting, fielding and pitching....not a ton do any sort of meaningful training. Baseball remains chronically undertrained in my opinion. The specialization that comes with year round travel ball (as opposed to kids getting different training effects by playing different sports) has made the situation worse in my opinion.
So, continuing to grow your knowledge base is key. Starting something on your own outside of working for a team or organization can be good too....just dont expect to make a ton of money for awhile.
Working with ex pros can be a challenge too. I have a friend who was a mid first round pick back when throwing 93 from the left side would get to that slot. He never did any weight training beyond pretty basic stuff, no olympic lifts, never threw beyond 120 feet ect. He was really negative towards all of those things, because, he never did and pro teams he played for didnt make him.
He taught mechanics and thats it. In talking to him I realized he picked up 10 miles an hour between his Jr and Senior years of high school. What did he do differently? He played water polo that whole summer and fall.
So, got into great shape, got very strong in the core, back and legs and threw a weighted implement (compared to a baseball) several hundred time a day. He didnt teach "other" stuff besides mechanics because he thought he never needed it....never made the connection.
My point is, it is a tough spot to be in, caught between parents who think travel ball games is enough and pros who think a player has to "have it" and thats it. So, if you are looking to just specialize in training for baseball the more internships and specialization you can attain the better.
If you also plan on doing standard baseball lessons, you might have a little more leeway.
When talking of doing work with someone like Cressey or some other "star" in the industry I bring that up only because....why not you? You need a healthy dose of self believe to embark on a crowded and competitive field. Not arrogance, but, self belief.
I bring up Cressey specifically because I know he does some sort of baseball training program for people in the field. I have met him and he is a very approachable humble guy. While working through one of his books I fired a question to him and he responded in a day, he certainly is busy and doesnt have to do that. But there are plenty of folks out there that would be very good professional mentors for you.
Read, read, read. Medical studies, Cresseys' books, Rippietoe, Boddy has a book out now, Set Pro stuff, anything you can get your hands on that relates to what you want to do.