Aphrodite was the Greek goddess of love and beauty, among other things, and was born from the sea and carried inland atop a giant shell. You can make a unique costume based on the natural elements with which she was associated, as well as artistic representations of her as seen throughout history. Store-bought Aphrodite costumes can have accessories added to them to make them more specialized, or you can start from scratch and create your own traditional or modern interpretation.
Not only was Aphrodite the goddess of love, but also of desire, fertility, the sea and nature. She was often associated with doves, swans, apples, scallop shells and mirrors, as well. Include accessories with your costume that relate to these symbols. Carry a stuffed dove or swan, or a bowl of real or fake apples with you. Bring a hand mirror and stare at yourself often. Attach small shells to your dress or put flowers in your hair to create a natural look.
One of the most famous paintings of Aphrodite is "The Birth of Venus" (her Roman name) by Sandro Botticeli. In this picture she is depicted nude, riding from the ocean on a giant shell with her long, blonde hair wrapped around her. You can recreate this look by wearing a nude body suit and a wig that reaches passed your waist. Add a golden circlet or braid to your head and perhaps carry a large shell that you can stand on.
The goddess of love was also the goddess of beauty, and considered one of the most beautiful of the Greek pantheon of gods. Wear makeup and even body glitter to emphasize your features. Put your hair or wig up so it frames your face, and include gold jewelry such as necklaces, bracelets and belts. Aphrodite was said to have a specially made, jeweled girdle that made her even more beautiful and irresistible. Include a corset or belt with your costume that can symbolize this.
You can base your Aphrodite costume upon specific myths about her by including specific accessories, such as a golden apple like the one for which she traded Helen of Troy in the myth of Paris and the fall of the Trojans. In battle myths, she was said to carry a helmet, shield, sword and lance. You can add these elements to your costume to be a less recognized form of the goddess.