Before you send wave upon wave of job applications, you should find out first if the companies you are applying with are even allowed to employ foreigners.
Writing an application in Thailand is a similar process as in Western countries. You will need a CV, a cover letter and not more than 3 references to complete your application.
Your CV should be clearly structured and easily understood by the reader. Point out who you are, what you have done, why you are the right candidate for the job and then stop! Consider that the average length of time an employer spends reading a CV is 30 to 60 seconds. Make sure to avoid spelling mistakes, as they are very unprofessional and bear in mind that a Thai CV does not require information about your family status. Try to put yourself in the shoes of the reader and do not forget that a well written CV is no longer than 2 pages.
You need a strong and convincing cover letter in which you highlight why you are the right person for the job. In Thailand, it is very important to address the right person including all his/her titles. By using terms and phrases that are meaningful to the employer, you will encourage him/her to continue reading and consider your application for an interview. If you're applying for an advertised position, include words from the advert and put them in bold.
The nature of the job interview will depend on the sector and culture of the organisation you have applied for. You should do some research into the company and know its main goals and intentions. Applicants are also likely to be asked about their values and goals at the interview. Many companies also offer an interview via skype.