Incoming freshmen needs help!

<p>I will be entering St. John's University in NY this Fall as an undeclared major. Classes start September 1, 2010 and I am here to ask for some advices from people so I can utlitize them precociously. As some of you may already know, I plan on transferring to a top college on the top 50s list as a Junior. I want to know as soon as the first day of classes begin, where should I start on establishing my extracurricular activities? Is it better to actually go to the professor's office hours, meet them well, and build a good relationship on that day (considering that it's kinda too early)?</p>