Google maps / transit routing smartphone apps do a pretty good job of this. I've not had trouble coming into a new city, asking Google maps to give me mass tran

Google maps / transit routing smartphone apps do a pretty good job of this. I've not had trouble coming into a new city, asking Google maps to give me mass transit directions and just following them. Most cities have real time bus/train trackers now that help you plan when to leave so you don't have to wait long.