Terminal Shuttle Bus in BJ airport

I am confused. On the airport website it is stated that the pick-up is as follows: T1: outside Gate 7 F1, T2: outside Gate 7 F1, T3: Gate 5 F1. On the Travel Chine Guide website, however, the ff information is given:
T1 -- Gate 3-5 on the 1st floor; T2 -- Gate 11 on the 1st floor; T3 -- Gate 5 on the 1st floor. What information is correct?
When getting on the terminal shuttle bus, how do I know in which direction the bus is heading as they are going T3, T2 to T1 and vice versa? Is there a sign or do I simply have to ask the driver?
Thank you for your quick reply.