I attended the selection day about 2 years ago so I don't remember everything, and in what order it happened or if they still hold the same style but here it goes anyway..
There was about 10 of us.
We got a brief introduction of the company (classic talk of who they are, what/who they are looking for etc.
A team-work exercise where we were split in two teams and asked to make a bridge out of paper and paper-clips.
We also had to make a quick presentation using a drawing board of some other member of the group.
Given a short test on our knowledge of the company (where does Easyjet fly to, who owns it etc.) and were told to wait outside.
Shortly after that got a one-to-two (two Easyjet interviewers) interview, asked a few questions and that was it!!
Can't seem to remember anything else. I'm sure there's a more up-to-date summary somewhere on Pprune.
Good Luck
Saggy