Zee Nova
My advice to you is to go through and search all the tips for OD and AD so that you are extra prepared . Also looking the part really helps - look on the Emirates sight at how the girls look and do your hair and make up just like that (presuming your a girl) If your a man make sure your suit is perfect , your clean shaven with neat hair .
I was a little surprised as I had my OD and AD in one day so I wasnt that prepared . I was there from 830 am - 730 pm ... Now I am just waiting and hoping .
Another thing I would suggest is getting there early and being in the first or 2nd row .... Having been to 2 OD / AD i saw that the majority of people chose were all in the front . Smile , pay attention and ask some smart questions so that they notice you in the growd and know your interested !
Good luck !