Hi Zebra89
The day started with document and height checks. Then straight into 2 group activities - 8 to a table with an assessor. They were basically seeing how well you worked with others and how adaptable you were, as there were changes to the activities half way through. I would suggest just be yourself, but make sure you get involved in the activities!
From there you had a lunch hour and were sent a text during that hour inviting you back to a panel interview (with 2) in the afternoon if you were successful. From my day only about a third of the applicants made it to the afternoon. The interview asked you scenario based questions, so I would suggest to have some answers ready.
Whilst waiting for your panel interview assessors checked the rest of your documents. I found the assessors to be very welcoming and helpful - all the applicants were very friendly too. It was an enjoyable day overall. They said it would be a two week wait to find out if you made it to the reference check stage, but thankfully for me I found out the very next day.
Now I myself am trying to find out what happens from here!
Good luck - I hope it all goes well for you.