Bangkok Airport Transfers
Once you exit customs and get to the greeting area, you will likely be approached by a lot of touts, including ones for taxi services.
Airport Link Train
The Airport Link Express train service can whisk you from the airport to the city in just 15 minutes, but depending on where you're staying, you'll need to take a taxi to reach your hotel.
To catch a regular public taxi, you must take the escalators or moving walkways down one level below the arrivals hall, exit the terminal building and the taxi queue will be on the curb. Under no circumstances should you accept a ride from any touts or "unofficial" taxi services. Real taxis have a red and white TAXI-METER sign on the roof. Many people have been robbed by seemingly friendly people offering them a ride to "a good cheap hotel they know."
Remember, when taking a public taxi from the airport, you pay the meter amount plus 50 Baht (1.68 USD). This only applies to taxis taken from the queue at the airport.
The official looking touts work for the airport limousine service, which will cost you twice as much as a regular taxi. If you wish, you can book airport transfer services in advance.