After clearing the rather slow moving Immigration lines at the airport, we decided to try the relatively new Bangkok Airport Rail Link instead of the usual taxi.
After walking a bit of a distance to the station, which is in a basement below the basement, we reached the ticketing machine.
We’re heading to Sukhumvit 13 so want to end up at Nana Station on the BTS line.
The ladies at the information counter suggested the City Line, which terminates at Phaya Thai station. The journey from the airport to that station cost THB45 per person.
From there the BTS to Nana Station should be just a handful of Baht.