To marry in Thailand, you have to first get into Thailand with a regular visitor’s visa or a Business Visa. You can also arrive with a VOA (Visa on Arrival) at the airport which gives you 30 days access to Thailand. Once there, you will have to find the rules and regulations of your own country (go to your own embassy in Bangkok) and prepare the paperwork to get a “freedom to marry” certificate stating that you have no prior obligations in your country.