The interview process begins with an application on their careers website. The requirements are well laid out and if you meet the threshold be sure to expect an email from them when the interviews begin. The interviews in my case took a period of approximately 3 months. The email came 6 months after I had applied. Patience is a virtue they highly value so you will wait. The interviews are, in order, Aptitude test->Psychometric test->Psychometric test->Medical->Oral interview.