Differentiating Male and Female Discus Fish

What is the easiest way to differentiate male and female Discus Fish?

Unlike carp where the males have a visibly slimmer outline and females have rounder, heavier bodies with softer and smoother fins, both male and female Discus fish seem to have the same body shape. Would there be differences in color, as I do know that male fish tend to be more gaudy and brightly-colored than the females?