For comfort, the best way to get
around is in an air-conditioned taxi. However, it is not
always the fastest way to go somewhere, especially when the traffic
is
bad. In addition, metered taxis (the vast majority and easily recognized with their "Taxi Meter" sign on the roof) are quite cheap - 35 baht (less than $1) for the first 2 kilometers and just 5 baht for each kilometer after that. There is a small charge for sitting in traffic.
Green and Yellow
Bangkok Taxis follow a color code of sorts, and the green and yellow taxis are considered the best because they are driver owned. The other colors are usually rented by the day by the drivers.
Have Someone Write You Destination in Thai
Unless you are going to a very well known destination, it is wise to have your destination written down in Thai script. There is no special exam to become a taxi driver in Bangkok and some drivers don't know the city that well. In addition, there is usually a language barrier as most drivers speak little or no English.
Tipping
In Bangkok, tipping taxis is not practiced, but rounding the fare up to the nearest 10 or 20 baht is common. If you plan on taking a taxi, it is wise to have some small notes - 20s and 100s - as many drivers don't have (or SAY they don't have) change.
Problems With Taxis
Problems with taxis are fairly rare although very occasionaly one will claim his meter is broken or some such thing. Avoid problems by watching to make sure the meter gets turned on. If the driver forgets, remind him or her (yes, there are some women taxi drivers, but not many). If they won't or say they can't, ask to get out but don't get angry and raise your voice.
Another way to avoid problems is to always flag a taxi down. Avoid taxis sitting near a hotel, standing outside the taxi and approaching every foreigner who comes along.
Taxi drivers are not required to take a fare, so once in awhile one will say no when you tell them your destination. Don't let this upset you. He may not have time before his shift ends.
There are plenty of taxis in Bangkok. Just flag another one down.
Many taxis drivers speed, weave in and out of traffic and tailgate. Most taxis do not have seat belts in the back but do in the front. If you sit in the front you must fasten the seatbelt.
Tuk-Tuks
Tuk-tuks are kinds of rickshaws with engines, unofficial symbols of Bangkok. The name comes from the sound of their engine. They have one seat and can accommodate three people.
There is no meter and fares must be bargained for. If you are thought to be a tourist who can't speak Thai, the first price is likely to be high.
You can bargain them down if you have an idea of what the fare should be; for example, if you have taken a metered taxi to the same destination before. Agree on a price before you go somewhere. If you don't, you are running the risk of being charged an absurd price and this could lead to problems.
While most people who are on holiday want to experience a tuk-tuk ride, many get tired of it. The vehicles are open air and subject to heat and pollution. Furthermore, they have no suspention and the ride is very rough. But should you give it a try? Yes.
Don't go anywhere with a tuk-tuk who sits around a tourist area and touts places to take you. If you go, you will likely be taken a place you are not interested in (a gem or tailor shop, for example) and even if you are, the price will be high so the business can cover the comission to the tuk-tuk driver.
As a rule of thumb, don't go anywhere with anyone touting something.