It is quite nerve wracking! But actually EasyJet was the most straight forward, simple, eficient and friendly Cabin Crew interview I have ever been to. And believe you me, I have been to pleanty!
Just smile and be yourself! The recruiters are all so nice!
I found the easiest way to relax was to talk to the other applicants. Try to help and encourage each other. EasyJet is so desperate for staff that they do not have a set number of crew they are looking for at each interview. If your good, and what they're looking for then your in!
Good luck!