Quick facts about Bangkok

1. The Traffic in Bangkok Is Terrible

Pick a hotel location that will limit the amount of time you need to spend in a car. My suggestion would be to stay off the Sukhumvit Line. This will make it possible to take public transit from the airport to your hotel and easily get around. You also don't need to spend large sums of money to be located in a really nice area.

Here Are Some Properties for >$100/ Night That I Would Stay In Again:

• Aloft Bangkok Sukhumvit 11
  A hip hotel right in the middle of the action, located off the MRT & BTS. The crowd can be a bit loud at night. This property has a rooftop pool with skyline views and a small night market outside every night.
  Verdict: Perfect for younger travelers who want a hip location.

• Hotel Indigo Bangkok Wireless Road
  Located right across from the US embassy, this hotel is quiet at night but ideally situated. A 5-minute walk takes you to the BTS, but at night the street is empty. The rooftop pool has a DJ on weekend nights, but isn't too crowded during the days.
  Verdict: Stay in the heart of the action albeit on a quiet street.

• Staybridge Suites Thonglor
  Thonglor is relatively far down the BTS line, but incredibly quiet and secure. It's not uncommon to see a Ferrari or other high-end cars heading home at the end of the day. This property has washer/dryer units in all of the rooms, a 20th-floor infinity pool, and free breakfast. They also have a free shuttle that takes you to the BTS whenever you need it.
  Verdict: Perfect for families and those who sweat a lot.

2. Don't Rent a Car to Drive in Bangkok

Instead of driving, download Grab (Uber does not work in Thailand). This will allow you to use a credit card instead of fumbling around in the back of a dark taxi for cash. Grab also delivers $3 pad thai at 2 am, or you can take a ride on a scooter across town.
Many Grab drivers offer private transfer or daily rate services. If you were impressed with your driver's service/vehicle, ask if they have a card.

3. Pack Clothes to Layer for the Heat

Temples and cultural sites will require covered knees and shoulders. The heat is pressing. Men should pack a pair of capris. For women, a super light shawl-type cover is useful. In both cases, you can also choose to purchase souvenir elephant pants or cool scarves locally. If you buy locally, prices are often unmarked. To avoid overpaying, here are common reference points (1 USD ≈ 35 THB):

• Elephant Pants: 100-200 THB

• Shawls/Scarves: 90-150 THB

When Looking at Clothing Quality, Stick to These Guidelines:

• Seam Quantity and Quality: Is it single-seamed, double, triple? How are the ends cuffed? How are buttons attached?

• Fabric Quality: Is it thick or thin? Does it feel rough when it shouldn't? Does the fabric look consistent?

• Check the Zipper: Zipper quality is usually indicative of overall quality.

4. Mobile Reception

Don't skip mobile access in Bangkok. Within a day, there will be a scenario where you will be walking in the heat and wish you could call a rideshare. If you would like to have cell service before you land, you can purchase an e-sim through AIS from your home country. You can also use Airalo to purchase a 1-week or 15-day unlimited plan for $10/$20 respectively.

For those that want to wait until they are in the country to buy a sim, Airalo is a great option.
My link will give you a $3 credit.

5. Hotel Status Still Matters in Bangkok

If you don't travel often, look at your credit cards, airline programs, etc. You may have a status match to a hotel chain that can get you a slight upgrade, welcome gift, or small amenity during your stay. US credit cards, such as the Marriott Bonvoy Boundless and IHG Select card, will give you a boost towards getting status, zero foreign transaction fees, and one free night per year as a perk.

What’s Next? Shopping & Eating!!!

I'll start with my favorite post-long-haul activity. It involves air-conditioning, minimal sweating, lots of food, and walking.

Grab a shower, then jump on the BTS (Bangkok Skytrain) and head to the Siam stop. To pay for the train, simply purchase a ticket from one of the machines. You can also buy a single journey fare or a Rabbit Card at the manned kiosk in any station if you plan to stay a few days and use the BTS frequently.

Be aware that the ticket machines usually only accept coins. If you decide to purchase a transit card, you will need your passport to complete the purchase as well as cash to pay for the transaction. One-way tickets are issued in the form of a card. You tap in to get on the train, then feed the card into the slot to exit (it will not return the card—this is normal).

MBK and More

Once you've made it to the Siam stop, follow the signs to the "Siam Discovery" exit. A 10-minute walk will take you to MBK, the OG Bangkok megamall. MBK was the largest mall in Thailand when it was completed in the 1980s. It's 8 stories tall, a full city block in length, and has over 2,000 shops.

Here’s What You Should Know Before Shopping in Bangkok

• Western Brands like Nike, Levis, etc., will usually be cheaper in the United States. Unless you've lost your luggage and plan on expensing your purchases, I'd skip the stores you will see at home.

• Outlet Stores are an exception. If you can find the color/size you like, you will pay 30-50% of retail price. Super Sports is my favorite outlet at MBK.

• Knock-offs: It should seem obvious, but places selling Ray-Bans for $10 or World Cup Signature Jerseys for $7 are selling knock-offs. Don't expect to score a pair of AirPods on the street for $20.

• Cash: See my note above about Thailand still being a largely cash society. Food stalls and kiosks in general may or may not take cards. Most storefronts, however, will—though you may need to pay an additional 3% processing fee.

• Negotiating Prices: Be prepared to negotiate in some kiosks at MBK and some, but not all, other shopping malls. If in doubt, ask if that is their best price. Chain stores will not haggle.

Once You’ve Had Enough of MBK

Once you've grown tired of MBK, it's easy to keep walking with minimal interruption to your air-conditioned comfort. Siam Discovery is diagonally opposite MBK, and you can use the skywalk to cross traffic on the 2nd floor.

Siam Discovery, Siam Center, & Siam Paragon

These malls are connected and filled with many western shops (Nike, Adidas, etc.). Apart from the food options and currency, you might not realize you're in Bangkok. If your luggage is lost, this is where I would head, as every shop will accept credit cards and provide receipts for compensation and warranty.

Siam Paragon has the nicest food options, but it can get extremely crowded. If you get hungry, I would walk across the street to CentralWorld.

CentralWorld

CentralWorld might be my favorite mall in Bangkok, mainly because of the food. Head to the top floor, where most of the food stalls are. To buy food, you need to load a card with some money, and at the end of your meal, you can recoup your 20 THB deposit and any remaining balance.

200-300 THB is more than enough for a meal. If you're a heavy drinker, double that to spend at the bar. Personally, I head towards the duck soup stall, which is directly to the left of the cashier on the mall side. It has a Michelin Bib Gourmand sticker.

Visit the Chatuchak Weekend Market (If It’s Saturday or Sunday)

Chatuchak is located just off the BTS. Take the train north to Mo Chit stop, then follow the path (and the people) to the weekend market. It's open on Saturdays and Sundays. Here you'll find clothes, food, and knick-knacks.

Why Chatuchak?

Chatuchak has far fewer tourists than many of the other markets a tour agent will try to sell you on. It's also closer to Bangkok than the typical "floating market" tourist traps. Plus, it only costs a couple of dollars to take the BTS—so why pay for a tour?

Most of the stalls will be willing to negotiate prices. If you’re considering buying multiples, use this as leverage to negotiate the best price.

Spend a Morning at the Temples

If you're not into shopping, I'd recommend heading to some of the best temples early in the morning to beat the heat. Wat Pho (the Temple of the Reclining Buddha) is a great place to start. It’s less crowded in the mornings, and you’ll need 200 THB in cash for the entrance fee.

Afterward, enjoy lunch nearby at Pad Thai Kratong Tong before moving on to either Wat Arun or The Grand Palace.

Don’t Miss Khao San Road

No trip to Bangkok is complete without a visit to Khao San Road. If you’ve been exploring temples all morning, you’ll be close. Bring a bit of cash, some patience, and your camera. There’s no real itinerary here—just experience it.

Explore Koh Kret for Something Different

If you’re in Bangkok for more than a few days, Koh Kret is worth exploring. It’s a small island best visited by bike or electric scooter.

Getting there will require a Grab. Once you’re at the drop-off point, head to the ferry pier. The ferry crossing is free, but you’ll need to pay 3 THB to enter the island once you arrive.