Also, usually you find a chart with the stations that are served at the bus stop and most liekely as well inside the bus. You just have to read where you get in, where you have to get out, count the stations and than count the stops while driving.
On ICE, you find little folded leaflets (on tables, in seat pockets, on chairs...). They show you the exact route of the train, and name all the serving stations. Again: just compare the names of the stations with your actual stops, and you know when to get out without speaking or even listening.