Information, please.

The most uselessly generic phrase in the English language is "Take care of yourself." Meant figuratively, it's usually a kiss-off bye-bye when you're walking away from someone you'd rather not have run into. Meant literally, as when said to someone who's sick, it's a paradox. On the one hand, no shit. On the other hand, if the sick person (who happens to be a type A control freak asshole) knew how to do that, they wouldn't need you to tell them to. So as such, without elaboration, "Take care of yourself" means nothing to me. I mean, the generic 'me.'

Seriously, how does one do that?