i'll have to agree about the boxes. personally, i wouldn't use them. strikes me as a cheap prop. too easy for it to backfire.
and congratulations on the interview. its a great feeling.
the thing about attitudes is that its such a fine line between confidence and arrogance and acting yet the results are vastly different.
true confidence has an attractive aura, its not something others see but they sense it. the man with confidence doesnt think about whether he's confident, the same way he doesnt think about whether he has a mouth - he knows its there so theres no reason to think about it. the act of thinking about confidence shows a lack of confidence. confidence is not 'hey-look-at-me" loud, doesnt act with the intention to draw attention to itself.
acting as if you have confidence is walking around with your chest puffed out, looking down your nose, trying to come across as aloof. and is cheap and unattractive. its gold colored plastic.
arrogance is overconfidence without being able to back it up, this is not only unattractive but repulsive.
my point is, that you need to be sincere in your actions and attitudes.
make yourself better for yourself. wear contacts for yourself. dress nice for yourself (and your interview).
take care of yourself not to get her attention, but because you have self-worth and you deserve to take care of yourself.
doing something to gain her reaction will come across as cheap and will actually push her away.
"In a ham and eggs breakfast, the hen is involved, but the pig is committed".
