Many strapless formal dress styles are gorgeous but are only practical for small busted women who like to stay still. Some bigger busted women need straps to hide their bras. Women who like to dance need straps to keep their dress up. Don't stand around all night pulling at the top of your dress or running to the bathroom to adjust your cups--put some straps on your dress. There are several ways you can add straps to a formal dress using materials that complement the dress and look like they were an original part of the dress.
Take some extra fabric from the hem or the seam to make matching spaghetti straps, double or triple thin straps or a simple wider strap. Use some matching trim, like lace, rhinestone, pearl or contrasting colour fabric, to make a simple strap or to make straps that crisscross in the back. If your dress has no trim and you like the look of the strap, find another seam or detail on the dress where you can put some more of the strap material to create additional visual interest. It's a way to take a plain solid-colour dress from boring to dramatic.
Turn matching or contrasting colour ribbon into tie straps complete with a bow to create a sweet romantic feel. Make sure the texture of the ribbon complements the dress fabric as well. Fashion a cross between a strap and a cap sleeve by softly gathering some matching or complementary fabric at both ends where it attaches to the dress. The middle will fan out into an abbreviated sleeve that still shows a great deal of shoulder.
Use a piece of fine mesh gauze or chiffon in a matching or contrasting colour to form a dramatic one-shouldered strap. You could even let it trail down the back to the floor for even more drama. Another use for gauze or chiffon is a halter neck strap. Matching trim or several rows of thin straps would also work as a halter. This is one of the best strap styles for anyone who is planning to be active, as the straps will not slip off no matter how you move.