The invitation to an evening wedding should give you the best clue about what to wear. If the invitation isn't clear, though, you can take cues from the time of the wedding and the location to figure out if you’ll need a tuxedo or a formal gown. As a general rule of thumb, weddings in the evening tend to be more formal, so even if the invitation says “casual attire,” you still need to dress up a little bit.

Women should wear a long evening gown in a darker, more formal color palette. Colors to consider are black, emerald, purple, ruby, brown and navy. Avoid backless dresses and plunging necklines -- the focus should be on the bride, not your dress. Style the gown with heels and match your clutch to the color of your shoes. Makeup and hair can include classic red lips and a sleek ponytail. Men should wear a tuxedo, or a dark colored suit, with a black bow tie, cummerbund and black cap-toe oxfords.

For a semiformal nighttime wedding, women can wear their favorite little black dress or a knee-length cocktail dress in jewel tones. If you wear a sleeveless dress, bring a shawl. Another outfit option is a dressy pantsuit. Accessorize with a silk clutch, heels and a statement necklace or cocktail ring. Men can wear a dark suit with a tie and brogues.

If the wedding takes place at the beach, the weather is probably quite warm, so dress accordingly. Men can wear a linen shirt without a tie, khakis cuffed at the ankle and slip-ons. Another ensemble for this evening fete is a summer suit with a linen shirt, printed bow tie and boat shoes. Women can sport a chiffon gown in a floral print paired with embellished sandals. Wear a pashmina shawl with your dress to keep warm. Hair and makeup should be as a natural as possible. You can also choose a delicate knee-length sundress with flat sandals and a printed clutch for an evening wedding at the beach.

Casual dress differs for day and evening. Because the casual wedding is in the evening, you still need to dress up a bit. Unless the invitation says “Jeans and shorts are welcome,” wearing them to an evening wedding is frowned upon. To be on the safe side, dress in business casual attire. Women can wear a wrap dress with pumps. If dresses are not your thing, style a pencil skirt or tailored pants with a nice blouse. Men should wear dress pants with a button-down shirt -- tie optional -- and a sport coat.