First of all, I submitted an application online through the career office of my university in November.
Then, I received an email inviting me in a telephone interview in last days of January. I had it four days later.
If you were successful, then, the next and final stage was during the same week. This one was composed of assessment centre, where you had to solve some problems cooperating in a group, and two interviews, where they assessed further your skills and personality.