Someone asked me about an itinerary for Singapore. So I did a quick list, this was tailored to flights out of Portland, Oregon (PDX). If you have something else you would like to know. Feel free to drop me a note and I will update this along the way.

I know from PDX Delta is the least stopover to Singapore.

PDX -> Narita (NRT) 1hr stopover -> Singapore (SIN)

I did a quick search on Singapore Airlines which is also a member of Star Alliance (United is part of it). (Real excellent airline. Trust me on this one.) http://www.singaporeair.com/

PDX -> LAX -> Narita (NRT) -> Singapore (SIN) I like this particular flight because it’s a A380
PDX -> SFO -> Seoul (ICN) -> Singapore (SIN)

Stay somewhere downtown. Marriott is in a real good location. Runs about 250sgd a night. (~180usd) the entire shopping area is here it’s called Orchard Road.

A rough map of where things are. https://drive.google.com/open?id=1Df5o5UA4nVgdY2CTiI7EyakkSWQ&usp=sharing

The unique hotel, Marina Bay Sands, that I told you about earlier. Pretty good location too. If you don’t mind the hassle of changing hotels, you can stay here for a night. This hotel has a infinity pool at the rooftop. Living in the hotel is the only way to get access to the pool and also it’s a observation deck on the top floor of the hotel (free for hotel guest). There’s also a laser show at this hotel every night. https://www.marinabaysands.com/

Nearby there’s a famous greenhouse nearby. Popular tourist spot. Called Gardens by the Bay

Merlion is also across the bay from this hotel walking distance. (free of charge)

Another famous spot also nearby is Singapore Flyer. Basically a giant ferris wheel. The singapore version of London Eye. http://www.singaporeflyer.com/

A lot of my friends use this bus when they are there. Unlimited rides for a day to tour around. http://www.city-sightseeing.com/tours/singapore/singapore.htm

But to go to attractions usually they just use taxi.

Singapore Zoo. Award winning zoo. Worth a visit. http://www.zoo.com.sg/ Jurong Bird Park is at a different location. Night safari and River safari and Singapore Zoo are all at the same location. River safari is new but it’s only popular because they have some new panda bear exhibit. (I think you can skip this one unless you have extra time.) Just head for Night Safari and Singapore Zoo, night safari is really unique. Jurong Birdpark if you have time. They offer a park hopper pass online check it out on the zoo link above.

Sentosa. Within sentosa there's a bus and train service. It’s free. http://www.sentosa.com.sg/en/attractions/ My friends that visit usually people will take shuttle one way and cable car one way. http://www.sentosa.com.sg/en/attractions/imbiah-lookout/cable-car/ Famous attraction at Sentosa.. this merlion is bigger than the one in the city and this has a laser show. http://www.sentosa.com.sg/en/attractions/imbiah-lookout/the-merlion/

The SEA Aquarium is also located in RWS. Heard its really good. Personally I haven’t been. http://www.rwsentosa.com/Homepage/Attractions/SEAAquarium

Some other interesting stuff in the area are like

Clarke Quay (extremely popular among friends that visit)
Chinatown
Little India

A lot of friends like to visit this mall. Personally, I have never been there.

Mustafa Center http://www.mustafa.com.sg/

Finally, Some local famous local food

Chilli Crab (Singapore Dish)
Bak Kut Teh (Singapore Dish- pork ribs soup)
Hainanese Chicken Rice (Singapore Dish)
Carrot Cake (not the regular sweet ones. It’s salty and doesn’t resemble a cake at all)
Roti Prata (Indian food)
Curry Fish Head (Singapore Dish)
Yakun Kaya Toast (breakfast/tea place)

Hope it helps. Let me know if you got more questions and I will expand the list and go on from there. That's all for now! :)