How to make smalltalk?
stonemetal: There are basically three sources of small talk.
  1. Things said previously in the conversation as in after asking what their major is a follow up where you actually know something about the topic.  It helps to be well rounded. 
2.  Your personal interests(note: for a geek this usually turns out badly if they haven't signaled interest in the topic.)
3.  Surroundings, posters for something happening on campus etc.Let it die.  It is the holding on to it after it is dead is what makes it awkward.  It is easier to approach them a second time if it dies cleanly the first time.