Well first off, thank you so much!!! Second, EVERYONE asks that and it's So easy! All you have to do is sew two darts into the spandex like you would a bodice. Mind you, these darts have to be pretty big, but if you get it right, the spandex sits on your body like a glove!!
I figured that was what was doing it, but had to be sure as side darts equaling middle separation didn't make much sense. Thank you so much this is going to help me with a couple different characters/costumes!!