Be yourself, be honest and do some research on your chosen Regiment. The recruiting staff will want you to succeed, the only person that can **** it up is you. I was in the same boat (albeit another inf regiment) in Jul '82 and made it through all the interviews etc. Back then Sutton Coldfield was used, not sure where they do it now. Fast forward 25+ years and I had a great career - good luck!
When I went to join the juniors I wanted to be a junior soldier in the paras. Cue interview with sergeant major after the AEII.
"So you only want to be a para, you're an ex-public schoolboy, here's a scenario for you. Your platoon and/or company commanders have received orders and come up with a hair brain idea how to execute the same. You and your fellow NCOs decide that the orifices are going to get you all killed; what would you do?"
I answered honestly, and was told to be an EWOP or go back to school and/or Welbeck and then RMAS.
Moral of the story relating to the Infantry...don't tell a CSM that you'd slot stupid officers.