Hi,
I dare say you'll find the open day very interesting, it is a great opportunity to get an insight into Ryanair and a great opportunity to chat with a couple of their current pilots.
At then end of the presentation, which will be at the end of the morning/afternoon session depend ing on which group you're in, you'll be asked if you want to give your CV to Ash, the pilot recruitment chap. I believe he then looks through the CV's and invites people to return for assessment.
Hope this helps,
JJ