Polo shirt and pant
Casual but not too causal.
i can only speak for woman here but..
don't show up with ripped jeans and sweater.
nice dress pant or black jeans ( no rips ) and a nice blouse with a cardigan or blazer over top. as for shoes, nice black flats or a shoe with a heel, just not too high. also make sure hair is done nicely and keep makeup to a minimun .
First impressions are everything!!
Nothing special to wear...