The first day of your summer-associate program is likely to go by in a whirlwind of activity. At the inevitable orientation session, there’ll almost certainly be a few speeches promising you an exciting and fulfilling summer. Someone will probably take you on a tour of the office, show you where the bathrooms are, and point you toward the break room. 

But even in the hustle and bustle of day one, it will be imperative to bear in mind the most momentous difference between where you’ve been...