How do you say 'go away' in German?

Answer 1

"Geh weg!" or (meant in a more rude way) "Hau ab!"
Well it depends who you're talking to, because you have to use verbs differently. If it's with someone you don't know well, then it would be:

Gehen Sie weg.

If it's someone that you're familiar with;

Geh weg.

Or you would say Geh doch weg, which is more like, why don't you go away.

Answer 2

Go away = "Geh' weg!" or "Hau' ab!"