Here's an ideal itinerary for 3 days in Bangkok:

Day 1:

• Start your day with a visit to the Grand Palace, one of the most iconic landmarks in Bangkok. Marvel at the intricate architecture and stunning details of this royal palace.
• After the Grand Palace, head over to Wat Pho, which is just a short walk away. This temple is famous for its giant reclining Buddha statue, which is truly a sight to behold.
• For lunch, head to Thip Samai Pad Thai, which is known for serving some of the best pad thai in Bangkok.
• In the afternoon, take a boat ride along the Chao Phraya River to explore the city from a different perspective. You can also stop at some of the temples and markets along the way.
• End your day with a visit to Khao San Road, which is a popular backpacker hub filled with street food, bars, and shops.

Day 2:

• Start your day early with a visit to Chatuchak Weekend Market, which is one of the largest markets in the world. You can find everything from clothing and accessories to souvenirs and street food here.
• After the market, head to Wat Arun, which is a beautiful temple located on the banks of the Chao Phraya River. Climb to the top of the temple for stunning views of the city.
• For lunch, head to Jay Fai, which is a Michelin-starred street food stall that serves delicious seafood dishes.
• In the afternoon, visit Jim Thompson House, which is a museum dedicated to the life and work of Jim Thompson, an American businessman who helped revive the Thai silk industry.
• End your day with a visit to Asiatique The Riverfront, which is a large open-air mall located on the banks of the Chao Phraya River. You can shop, dine, and enjoy live entertainment here.

Day 3:

• Start your day with a visit to Wat Traimit, which is home to the world's largest solid gold Buddha statue.
• After the temple, head to Chinatown, which is a bustling neighborhood filled with street food, markets, and shops. Be sure to try some of the delicious Chinese-style dishes here.
• For lunch, head to Thipsamai Pad Thai, which is known for serving some of the best pad thai in Bangkok.
• In the afternoon, visit the Bangkok Art and Culture Centre, which is a contemporary art museum that showcases the work of local and international artists.
• End your day with a visit to the famous Patpong Night Market, which is known for its lively atmosphere and cheap shopping. You can also find plenty of bars and restaurants here.