First time doing an Assessment Center - Any tips?

Hi guys,

Little bit stressed right now as I have a BB assessment center coming up (off-cycle, London). I was wondering whether any of you guys have assessment center experiences that you would like to share, and any tips/tricks you have and mistakes you have made, and stories you might have heard of. 

Another thing I was wondering is, what is the success rate of these AC's? Do they give an offer to everyone who is outstanding? Or does only one candidate get an offer during each AC? What type of background do other candidates have? And how in-depth must my financial skills be? (WACC and valuation methods I know well, but liquidity ratios, bond valuation methodologies etc I do not know). Have the AC later this coming week. 

Any advice would be great, thank you :)