Get to know your professors
Because you'll need them by the time you're in your last year.
When it comes to extending deadlines, combing over problems in coursework or looking for the perfect piece of secondary reading to complement your essay - a good working relationship with the tutor will pay off tenfold.
Don't suck up though, nobody likes a swot. And know where to draw the line with how close is too close. Don't let the glamour and awe-striking nature of academia loosen your senses too much. They're not deities, they're teachers.