How do I get from Greensburg to Pittsburgh by bus?

Okay, I'm going to the University of Pittsburgh At Greensburg Sunday night, and I need a ride home the next day. I know the Westmoreland Transit runs buses, but I can't understand their pdf on their website. I know I'll have to get on another bus to get home, but how do I get from greensburgh? I'd prefer to get off at Oakland, but downtown would work. Thank you.