Bangkok is one of the most popular cities in Southeast Asia for tourists.
As a big modern city, amenities are abundant in Bangkok but there is always something you can do to make your trip easier. Here are some of my tips:
Thailand uses Baht, and there are plenty of ATM around the city that’s safe to use. For currency exchange, Super Rich is a trusted chain that many exchanges with. Thailand is mostly a cash-based country, so you best have some money on you when you arrive for transport and food.
You can pre-purchase your sim card or WiFi device for Bangkok easily, and there are plenty of counters in airport that sells them.
There are a few key transport services in Bangkok, most common for tourist is BTS, which has a transport card called the Rabbit card. To save time, you can book through Klook and collect it by Klook counter by the airport skytrain terminal.
Grab is used extensively in Thailand. While metered taxi might end up being cheaper, the fixed price and being able to select the destination on GPS makes it a preferable platform for many. There are often promotions, too, making it more affordable. Do note that toll fees are not included in the car fare, so communicate with your Grab driver about it when you get on, especially from the airport.