The tie and possibly suspenders can let some of your personality show through. But, if the interview is very conservative the man can simply keep his coat closed. Men should remember to keep their hair neat, no matter what length it is. They should also find out what the company thinks about facial hair. Also, interviewees must keep in mind that many of the more conservative corporations are not tolerant of men wearing earrings.
Women have a few more options when deciding what to wear.
Suits are always appropriate, but women have more options in color than men do. Women can also wear some tailored dresses to interviews. Although most professional fields prefer women to wear skirts to interviews, remember that some favor pants. If you decide to wear a skirt pay close attention to the length. This isn't Melrose Place, ladies.