rehearse answers to the usual "difficult questions"
so- why should we hire you?
so- how do you think ur gonna cope, jumping from a light twin to a 737, is it not a big step up for you?
Why flying? how long have you been interested in it?
Dress code, if I was you id try and get hold of a pilot's uniform from somewhere, complete with epaulets and hat, show them u mean business.