Be prepared for questions such as
- what can you bring to the event services office?
- what is your best strength?
- what is your biggest weakness? <- almost EVERY interview
- what are your goals/what do you hope to gain from this opportunity?
- tell us a little about yourself? <- limit it to hometown, college, family, any graduate school...fundamentals
Otherwise, make sure you have one or two really good questions written down to ask them. One above is good about "what will I be able to learn during this experience?" (use the word learn, not gain...gain implies a selfish attitude rather than one of teamwork). And definitely thank them, just like above. As a matter of fact, on your notes, write that statement of gratitude someone above said verbatim.