Looking for information about ITP specializations

So I'm a visitor student (international exchange) at USC in the major of Computer Science at Viterbi School.

I stumbled upon the ITP specializations website and got interested in one of them.

However, I'm not sure how I am supposed to proceed to claim a specialization after attending to its respective classes.

1. Does this incur an additional fee?
2. Am I supposed to take the classes first, and then request the specialization status / diploma, or is it the other way around (= should I tell someone about my interests in the specialization prior to taking its classes)?
3. Is there any contact I should e-mail to better get informed about this?

I searched the archives of this subreddit but couldn't find anything related to that. Thanks!