All you need to know to visit Bangkok

To get around Bangkok, you are spoiled for choice! While occasional travelers often use tuk-tuks, which remain the emblematic means of transport in Thailand, and Bangkok taxis (insist that they activate the "meter"), traveling in the Thai capital by metro allows you to avoid traffic and be in air-conditioned trains. There are several rail networks in Bangkok: the BTS or skytrain, the overhead metro, the MRT or underground metro, although it now has stations and even entire lines in the open air, and the Airport Rail Link, which connects the capital to Suvarnabhumi airport, not to mention the Red Line suburban trains that go to Don Muang airport. You can also use motorbike taxis or take Bangkok buses, although the lack of line maps and signs in English makes their use a little complicated for a tourist. Fortunately, on the site, I created a Bangkok bus search engine to go to the main places in the city. And otherwise, there is the very practical free ViaBus application.

There are also, and I must say that I use it more and more often, there are smartphone applications to order a taxi or a VTC in Bangkok: InDRIVE, BOLT or Grab. And also Muvmi to order an electric tuk-tuk (I haven't tested it yet)

Another option: take the river shuttles that run on the klongs, the small canals that cross Bangkok or those of the Chao Phraya Express that navigate on the river. The most daring might try the Pun Pun Bikes, the Bangkokian Vélibs. But avoid the main roads! To go to or from Suvarnabhumi airport, I advise you to take the Airport Rail Link at Phaya Thai station (served by the BTS) or to take a taxi or even the S1 bus line, if you are coming from Khao San Road or the Grand Palace area. To go to Don Muang airport where most domestic flights depart and arrive, there are express buses that very regularly connect the airport to the Mo Chit BTS station, the Northern Bus Terminal, Khao San Road or the Grand Palace or even the Victory Monument. Don Muang is also accessible by train but be careful, trains in Thailand are regularly late except for those on the Red Line which run very regularly and also serve Don Muang airport! A free shuttle bus service runs between the two Bangkok airports (from 5:00 to 22:00 - 1h30 journey, more info here)

All the practical information on transport in Bangkok is HERE.
Beware of tuk-tuk drivers who hang around in front of Wat Pho or the Grand Palace and tell you they are closed, only to offer to take you somewhere else. In the vast majority of cases, nothing is closed, they just want to take you to shops that reward them with gas vouchers for each customer you bring. Sometimes you will even find yourself in jewelry stores passing you off as fools.