Don't worry about your body
You don't have to be gigantic with egg-carton abs to be Superman, and you needn't be a 7 ft tall beefcake to be Bane. The cosplay panel assured the audience that their personal body quirks shouldn't stop them from dressing as a character they like.
"See how you can make it work," suggested Indiana, "and remember, corsets are your friend."
Although some costume manufacturers aren't very plus-size-friendly, the panelists all agreed that the idea is to represent something about that character. So, if you want to go as Poison Ivy, for example, find a lycra costume that will make you comfortable.