The best months to visit Bangkok are December to February; these make up the cold months in which discovering the city by foot will not involve drowning perspiration. During the evenings at this time of year temperatures have been known to drop below 20 degrees Celsius.
Advance booking is the best way to get cheap flight to Bangkok. Book 4 to 6 week in advance to grab cheap flights. Airlines such as Cathay Pacific Airways, United Airlines, Qatar Airways and Eva Airways offers great discounts on airline tickets. From the airport taxis are the easiest way to get from Bangkok's Suvarnabhumi Airport (BKK) to downtown. The Airport Bus Express is another option.