Time needed to travel: at least 2 months
Southeast Asia is a magical place. Thailand, Laos, Vietnam, and Cambodia have become more and more popular for travelers with the passing of each year. These countries are perfect for everything from the food to clothes to transportation is so cheap compared to the States, Europe, or Australia. SE Asia has so much to off backpackers from beach parties in Tahiland, to ancient temples in Cambodia (The Temples of Angkor), tubing down rivers in Laos, and boat trips in Vietnam ( Ha Long Bay), just to name a few.
Almost every flight coming into Southeast Asia flies into Bangkok, Thailand. Us citizens do not need a visa to enter Thailand. Most backpackers head straight to kao San Road from the airport. You can ge there from the airport in a bus or a regular taxi. Once you show up on Kao San Road you will be able to notice that the taxi service around Bangkok is actually tuk-tuks. When you get your first ride in a tuk-tuk, make sure that you negotiate with them that you want no stops! They will try to give you a price that includesstopping at a clothing store so that you can buy tailored clothes. These drivers get paid for you buying things. 
Kao San Road is a backpacker heaven. On and around this road are all sorts of hotels. A single room with your own bathroom costs around $7 a night! You do not need to reserve a room ahead of time, because most places to not take reservations. All you need to do is show up and check availability of the hotels. There are all sorts of restaurants and bars on Kao San Road too. You can eat Pad Thai or pancakes on the street for about 10 Baht or 50 cents American. It is so good that you will want to eat it again the next day! I found it kind of hard to 
meet travelers in Bangkok, because people were already in groups. I would suggest to stay in Bangkok about 2-3 days and then get out of town!
In Bangkok, you have a couple of options when thinking about what the next step is on your trip:
1. Go north towards Chiang Mai and then travel through Laos, Vietnam, and Cambodia. 2. Go east towards Siem Reap, Cambodia, then Vietnam, Laos, and back south into Bangkok 3. Head straight to the islands of Thailand from Bangkok. The half moon and full moon parties are the highlights of heading straight to the islands. Here you will find a party with 10,000-15,000 people during the peak months of travel!
When I traveled SE Asia I took option one. I think it was definitely the best option. Then when you are done traveling you can hit the beaches and just relax!
On Kao San Road there are plenty of travel companies that will give you information regarding flights, 
buses, and train rides for each option that was listed. These travel companies can get your visa's for Laos, Vietnam, and Cambodia. You can get your visa's at the boarder of Laos and Cambodia, but it is always better to get them before you arrive at the boarder from my experience. Allows remember that you can do everything that these travel companies are doing for cheaper by doing it yourself. So if you want to buy a bus ticket, just go to the bus station and buy it instead of using a middleman. You will save money by not paying commission to the travel company. On Kao San Road you will get sick of seeing these ladies trying to sell these wooden frogs that is seen in the above picture! Its almost like a comedy show!
One of the best times of the year to go to Southeast Asia is during the New Year (not Jan. 1). The New Year in Thailand, Laos, and Cambodia is actually in April. From April 13th to April 15th they celebrate their New Year or as they call it in Thailand Songkran. The New Year festivals include a water fight in 
the streets that are daily starting on the 12th. The best place to go for this is Chiang Mai, Thailand. There is a moat that surrounds the city with an endless supply of water. It doesn't matter if you are wearing your backpack, have a water bucket, or eating in the street, you are going to get soaked for just walking down the streets. All the bars and restaurants along the moat have music, beer, and huge drums of water filled with ice
water to throw on all the motor scooters and bikes that are passing by. Don't miss this party!
Most popular ways to travel SE Asia
Bus
Buses are the most popular way to travel through SE Asia, because it is the most economical way and easy way to travel! There are bus stops in every city no matter if the city is big or little. You will find out that not only do backpackers take the bus, but you will be riding the bus with a lot of the locals too. It is very east to buy bus tickets. Every guest house or hotel that you stay in will have information on how to get a bus ticket to your next destination. Buses are virtually the only way to travel through Laos and Cambodia.
In Vietnam, they will offer you a package deal on your bus tickets. When you start in Hanoi you will be able to choose 5 stops on this package instead of buying individual tickets on your way to Saigon. You will be able to save a little bit of money on this option. Every hotel and travel agency in Hanoi will have information on different packages that are available. In Thailand, Laos, and Cambodia I would suggest to just buy one way tickets.
When you are traveling on the bus it will make stops at "restaurants" for bathroom and food breaks. These breaks usually last about 15-30 minutes. You can buy drinks and food at these places. There is usually no other places to eat around the stop, and the owners raise all the prices on everything. I would suggest to bring your own drinks and food on the bus before you leave on your trip. They also have a lot of people trying to sell you things while you eat.
Train
The train is very easy to use in Asia. There is a train that runs through Thailand, and also a different train system that runs through Vietnam. Both systems run throughout the whole country. The train is not a popular option to travel through Laos and Cambodia.
In Thailand, you are able to take the train out of the main terminal in Bangkok down to the south to get to the islands or you can head north towards Chiang Mai. They are both easy trips. The train that runs through Thailand is nice and not a bad travel. In Vietnam, you are able to take the train all the way from Sapa (northern boarder) down to Saigon. You will be able to make stops at a different locations along the way. The train is usually faster than taking the bus.
Flying
If you do not have at least 2 months to travel through SE Asia then it might be a good idea to fly to some places instead of traveling a day to get there. There are flights that run daily from Bangkok to almost any destination in SE Asia. Thai Airways is the best airline to choose from. This airline flies both domestic and international. If you are looking to fly to the Temples of Angkor in Cambodia there is an airline company Siem Reap Airways. They also can fly domestic and international.
Flying definitely is more expensive than taking the bus. Almost no budget travelers will be flying within SE Asia except for flying down to the islands of Thailand. For Example, a flight from Bangkok to Siem Reap, Cambodia costs around $150 US Dollars one way. A one way bus ticket costs $17 US Dollars. The flight probably takes about 45 minutes compared to 8 hours on a bus.
Boat
Boats are a popular way to travel in some parts of SE Asia. It is a fun alternative to the bus or flying. The type of boats you will take vary depending where you are in Asia. In Vietnam, you might have a big boat where you can stay the night on board. In Laos, you will have a smaller boat that you can't sleep on.
One popular boat trip through Laos is called the "slow boat." The slow boat travels from Xouei Xai, Laos to Luang Prabang, Laos. You can book this trip in Chiang Mai, Thailand or in Luang Prabang, Laos. You will travel about 6 hours during the day for two days. You make one stop at night in a place called Pak Beng. This is just a small village that breaks up the trip. There are a couple of hotels here and places to eat, but that is all that is in Pak Beng. I had a great time on the "slow boat." You are able to meet new travelers, relax, see great scenery, and experience another way to travel. Some travelers don't like the slow boat, because it is two days on a boat. If you just take it easy and enjoy the trip you will like it!
In Vietnam, there are two boat trips that you can take. Halong Bay is a great place to take a 2-3 day boat trip through the dragon islands. These boats have beds and showers so that the boat doesn't have to dock for the night. Your boat will actually just drop an anchor along side other boats in the sea. There are also boat trips down by the Mekong Delta in southern Vietnam that are very similar to the trips in Halong Bay.
Bike
Biking through SE Asia is slowly but surely growing in popularity with travelers. Biking through a country 
is the best way to actually get to "know" a country. The experience from biking through a country is unforgettable! You actually get to take in the scenery of the country by taking your time each day looking at your surroundings. You also have to learn how to communicate with the locals outside of bigger cities. These locals more than likely don't know English so you have to find a way to communicate with them.
I met 4 travelers when I was staying in Luang Prabang, Laos. They invited me to join them on an adventure. We all 5 bought mountain bikes from a local tourist office. Once we bought the bikes we gave our friends who we were traveling with our back packs to have them take them to Vang Vien (the next main city in Laos). We talked to locals and they said we were crazy, but we decided we were 
going on a 3-4 day bike trip! I have never had more fun being out in the middle of nowhere riding a bike! We rode through the mountains of Laos with no problems (except 4 flat tires). The people in the countryside were so nice, and even through we couldn't communicate with them they would help us repair our flat tires. During my trip I saw 2 other people riding through Laos on a bicycle by themselves. It is a great way to travel and I would suggest doing it on your trip!
Popular destinations in SE Asia
Thailand: Bangkok, Chiang Mai , Phuket, Ko Samui, Ko Pha Ngan
Laos: Luang Prabang, Vang Vien, Vientiane,
Vietnam: Sapa, Hanoi, Ha Long Bay , Hoi An , Saigon, Nha Trang
Cambodia: Phnom Phen, Siem Reap
