I feel like the shoulder pads might look a bit odd as bust cups, if you've done it before and it looked good go for it, if not I would recommend getting some bust cups at Joanns (if you have a Joanns) or using an old bra. I think the bust cups come with directions xD Not sure. You could even get a pattern that had directions on putting in bust cups. And if I were you I would add boning to the dress...? If you were comfortable with doing that.