One way to make a Greek goddess costume is to buy the right amount of fabric, gold cord, two brooches and fabric glue to create the shape of the costume. If desired, Greek-style trim can also be glued to the costume.
Common fabric color choices for Greek goddess costumes are white, purple and cream. Purple was the color worn by Greek royalty, and white was for common citizens. Once the fabric is chosen, measure it from the shoulder to the floor, and then double that length so there is enough for the front and back of the costume. If necessary, trim the width of the fabric. Glue any desired trim to the edges of the fabric before doing anything else.
Cut the fabric into two panels, and drape them over the shoulders, using the brooches on each side to connect the two pieces. The brooches can also be made at home by cutting a piece of cardboard, gluing rhinestones or other decorative items to it, and then gluing the cardboard to a pin. Trim the bottom hem and sleeves for a cleaner look, and then criss-cross the fabric under the arms. Use the gold cord to tie the costume in place.