Wear colors that match with your skin tone. Darker colors will look more formal than lighter colors. A little black dress can look really chic an can be glamoured up with accessories. Other colors can also be stunning, look seasonal colors for inspiration. Combine your dress with some dazzling high heeled pumps or open sandals in a color that matches with your gown. Never wear a large bag but go for a small and elegant evening bag. If your dress is in a basic color like black you can also choose to let your shoes or your bag stand out by letting it be in a bright color. Go for some eye catching jewelry, especially if you wear a simple gown. Wear for example a beautiful silver or golden bracelet with some flashy earrings. A beautiful necklace is also an option, in this case don't let your earrings be big and make sure that the necklace doesn't compete with your neckline. Put some effort in your hair and put some makeup on. During evening events your makeup can be more dramatic. Make your eyes or your lips pop out while still looking natural.