Formal suit (no shiny stuff, try to be conservative), dark charcoal grey, black or dark blue, conservative tie and formal shoes. Preferably short hair, no pony tails and preferably white shirt inside.
For Women
We would also recommend ladies to wear something like a (dark conservative color) mid-length skirt suit with a blouse or a shirt and a jacket on top. A full length pair of pants is also a good idea. A regular port folio (black, burgundy or dark brown) for keeping documents is necessary. Preferably shoes rather than pencil heels. Try to look like one of those business executive ladies.