This is probably one of the wrongest pieces of advice I've seen in social media blogs. I'm not saying it isn't true, but it's like asking a blind man to paint what he sees in the mirror.
Most people don't know who they are. And for companies and brands that's also true. So this kind of advice ends up being utterly redundant.
Let's go back to basics. In order to work it all out in the social media world, you must first discover yourself. There's a subtle yet crucial difference.