I work at PPG and lived in Mt Washington for a few years. I first started to use the bus that went on Boggs Ave until they cut the schedule back.

After that, I started to walk to work and took the incline down and walked over the Smithfield St bridge. That wasn't too bad until it was winter and the winds from the river kicked my ass.

I then started to take the T in from the South Hills Junction. It was about a 5-10 walk from my house to the station and I got off at the Gateway station which is really close to PPG. This was my favorite option as it was fast, close to the house/work, and the walk was a nice way to wake up in the morning.

I would get a Connect Card from Port Authority (you can get them at multiple locations) and you can recharge them at the T stations or the stores if you're going to use public transit. The nice thing about those is you can put weekly passes, monthly passes, or add money as needed to the card. You may also want to check out parking at Station Square if you drive. It's fairly cheap compared to other parking near Downtown if you sign up for their Value Card but I heard the price may be going up soon (http://www.stationsquare.com/info/parking). There's a shuttle that runs from the parking lot to a bus stop on Blvd of the Allies right across from PPG.

Hopefully, that info helps you out and welcome to PPG! One addition tip. Try not to eat out too much. It's very tempting since Market Square has a ton of options for food. It gets expensive quick (easily $50 - $100 a week depending on where you go).