Do I need to book my hostels in advance?

During the peak season (Dec-Feb), book at least 3-4 days ahead. During the shoulder season, 24 hours is plenty.

Is it safe to drink the tap water?

No. Use a reusable bottle with a built-in filter or buy large jugs of water from 7-Eleven to refill smaller bottles.

Planning a Backpacking Route Through Southeast Asia

Focus your route on a 'banana pancake trail' loop starting and ending in Bangkok, allowing 6-8 weeks for a comfortable pace. Don't try to see every country; prioritize 3-4 countries to avoid spending your entire trip on buses.

Establish your anchor city. Book your arrival and departure flight for Bangkok, Thailand. It is the cheapest regional air hub, meaning your flight will likely cost $300-$500 less than any other entry point.
Map your 6-week loop. Follow a clockwise or counter-clockwise loop: Thailand -> Laos -> Vietnam -> Cambodia -> back to Thailand. This avoids 'backtracking,' which eats up time and money.
Check visa requirements early. Check the entry requirements for Vietnam and Cambodia specifically. Vietnam requires an E-visa applied for at least 7 days before arrival, whereas Thailand and Laos often allow visa-on-arrival for many nationalities.
Prioritize transport methods. Use 12Go.asia to compare prices between buses, trains, and budget airlines (AirAsia/VietJet). Never book transport more than 48 hours in advance so you keep your flexibility.

Do I need to book my hostels in advance?: During the peak season (Dec-Feb), book at least 3-4 days ahead. During the shoulder season, 24 hours is plenty.
Is it safe to drink the tap water?: No. Use a reusable bottle with a built-in filter or buy large jugs of water from 7-Eleven to refill smaller bottles.