Summarize this article:

In some cases, such as opening nights and special "black tie" events hosted by the theater, attending a stage production might require formal dress. For these occasions, you should plan to piece together some of the more elegant selections from your wardrobe. Typically, black and white will be the best chromatic choices for such events. If a production is advertised as "black tie" or "white tie," or if it's an inherently formal type of event, like an opening night or opera, this means that formal dress standards are expected. In contemporary times, the rules of formal dress have changed somewhat. One effective strategy is to dress in a manner similar to the way you would for a night out at an upscale restaurant, or perhaps even a professional setting. If you're a woman, this may be a mid-length skirt or pant suit, although evening wear like a tasteful cocktail dress will create a more alluring look. Men should choose a well-fitting suit in dark, neutral evening hues; shirtsleeves with a tie and pressed slacks are also generally acceptable. For modern formal theater events, the same attire you might wear to a wedding, funeral or charity dinner will generally be sufficient. Finalize your formal look with necklaces, bracelets, watches and other jewelry. Wear closed-toes shoes with appropriate stockings or dress socks, even in the summer. Carry a matching purse or handbag for small belongings (if you have a larger bag that might take up too much aisle space, leave it at home). And, of course, be courteous to the actors and other patrons and keep cell phones and other devices put away until after the show.  Oversized or abundant jewelry can look gaudy and distract from a sharp outfit. Binoculars are permissible if the theater where the production is being staged is quite large, or for those with who have trouble seeing at a distance. Because they don't make noise or emit light, like phones and camera, binoculars are considered normal theater accessories. Your hair is also a vital part of your appearance. Scruffy hair that is tangled and in need of a wash can spoil an otherwise dapper ensemble, so be sure to wash it the night before or the morning of the show. Buns, loose curls or straightened hair is encouraged for women. Men should keep hair tamed with pomade, slick or part hair that is grown out or pull long hair back neatly.  Consult a style guide for options on how to style hair of your consistency and length. As silly as it sounds, hats and tall hairdos can obstruct the view of the people sitting around you. As a rule, hats should not be worn indoors, and you should think of the other theater patrons when coiffing your locks.

Summary:
Pick out flattering formal attire. Wear clothing that is appropriate for a special event setting. Accessorize for your ensemble. Wash and style your hair.