I don’t quite get this ‘swag’ thing.

I don’t quite get this ‘swag’ thing. Does it come a kind of curtain that dips down? Is it like the walk someone imitates from an old western? Does it mean you’re part of a group? Does it stand for something like: Single Women Are Great? Seeds Will Actually Grow? Sexy Wrinkles Are Gorgeous! If someone says, “I’ve got my swag on” does this mean they are wearing deodorant, underwear, or cologne? Or does it mean they have attached a new persona to their old tired self? So help me out. If I should have a swag, please connect me to the Swag Guru. I don’t want to be the only ‘swag-less’ girl in this big world.