Customarily, a dinner party at home or at a restaurant has an even number of men and women guests. Although there is no need to cling to this tradition, husbands and wives are usually seated separately and the seating arrangement alternates male–female–male. The male guest of honor usually sits on the right side of the hostess and the female guest of honor sits on the right side of the host.
In a formal setting, the host often provides name cards at each place setting above the service plate. Guests look for their own name and take that seat. In an informal setting, the host indicates who should sit where. The wisest course for the guest is to wait until told where to sit or ask, “Where would you like me to sit?”
The times are changing, and a host may invite his guest of honor to take the seat with the best view, or he may ask his guest to sit wherever they wish.