When you arrive at the airport go to Terravision desk at the arrivals hall. Here you can buy tickets. The staff will explain you where the buses are.

 

The tickets (one way) sell for €6,00 at the ticket office in Rome Termini

If you already have a ticket, present it to the Terravision rep (or the driver if there is no rep). Climb aboard and select your seat. The coach will leave once all passengers have arrived.

 

Terravision advises all passengers to be at the stop at least 10 minutes prior to the scheduled departure time.

 

For more details check out the service timetable: http://www.terravision.eu/pdf/ciampino_timetable.pdf