This means to be getting buck-wild and straight stupid up in a place. To be the life of the party. It means you're gettin' drunk and actin' a fool. Usually associated with local celebrity "Smooch Marlowe", who coined this phrase while at a bar drunk when we asked him on the phone what he was doing.
Us (to Smooch over the phone): "Smooch, what are you doin'?"
Smooch Marlowe (at the local bar, drunk): "I'm rockin' it like a champion!"
Wearing a fit that looks good on you and being confident about it. You don't have to be a model to rock it out in a fit and look good as fuck as long as you're like "i'm me"
Simone is a little chubby but she's rocking it out in those boots with her jeans tucked in and that sweater, she looks great and she knows it!