You don't have to hide your body shape, you just have to select a dress which does not add attraction to your problem area. There are a few things that must keep in mind while choosing Plus size dresses, here they are
A dress which is too tight or loose will add on a few pounds to your look. Go for a perfect fit, it has the magic to transform you from frumpy to chic in seconds.
Choose accessories that will enhance your look, example go for a chunky necklace if you want to keep the attention to your upper body and divert it from your lower body.
Go for prints and patterns that will make you look slim. Opt for small prints and vertical lines they create an illusion of slender body. Opt for heels, they add instant sexiness to the dress. If you have musculr legs avoid dresses that end right on the calves.
Checkout WePromDress for plus size dresses.