Usually said after saying something smart or intelligent.
A longer version of the sentence is 'Up here for thinking, down there for dancing, out there for shaking and down here for making' Usually one would point to their head then feet for the shortened sentence. If lengthened one should then shake their hands and then point to their mid section while saying the last two things.
A girl with a very sexy body but an unattractive face... This phrase is generally uttered by men who examine the posterior of a lady as they drive by, On the approach they say "Oooohhh" and if her face does not match the beauty of her posterior as they pass they will say "Naaaaaa", hence Una.