What always works is a navy-blue or black suit.
Black leather classic shoes, but NOT laquered. They must be clean, also the underside. Wear a white or light blue shirt.
A red tie, without prints on it.Ever Watched the Presidential debates? They always wear red ties because this makes a person look confident, strong and a "leader" without being "dull".
Facial hair is OK for already a while now people. A ringbeard is actually quite distinguished, as long as your beard is trimmed and your haircut is tidy. People who still believe that having facial hair will stand in the way of a job have some catching-up to do, or live in the US.
I have been previously involved in recruiting/selecting for Flight Academies and Airlines.