Wall Street career paths/ progression?

Hi. Could anyone share their two cents on how to break into Wall Street from undergrad? I want to go into HF or similar, probably not staying in IB. But I have heard that IB is usually a stepping stone to these jobs? Is it difficult to go from undergrad straight into these other careers? Even if I stayed in IB or another industry, how long would it take to get to associate (w/o and w/ MBA), vice president, then MD? If I decided to leave Wall Street after 3-5 years, what could I do afterwards? Work at a large corporation in the finance department or work on a start-up? What opportunities will get opened up to me from a few years on Wall Street. What is the next more lucrative thing to do if not staying in IB until MD position? What is the next best interesting/fun/ rewarding job if not staying in IB? Even on Wall Street, how difficult is it to switch industries? Thanks.