Pretty easy to get. I think I got this around my 50th game. Just play well and answer interview questions with a or b since these tend to raise your fan base the most. Also donating vcs to chairty like nba cares help. Winning player of the game, week, and month also really help. Another thing that really helps is every endorsement you get and you just earn those through playing well. I think you get one when you start your first game, you get one for every time your player of the month, just stuff like that. Just play the my career mode and you'll get it.
EDIT: There is also a facebook game called nba 2k MyLife and an app for both androids and Iphones that allows you to earn VC and fans for your player if you connect them.