When should "literally" be used?
Solution 1:
Hmm. I think 'literally' could be used when the listener might otherwise think you are exaggerating, even if not employing a figure of speech.
I literally spent hours stuck in traffic this morning.
i.e actual hours, not rhetorical 'hours'.
Solution 2:
You can say you are literally starving to death if you have not eaten for a week or so.
I personally use literally to emphasize a fact. In my opinion It actually took him an hour is less strong as It literally took him an hour - can you believe it!?
Have a click through to this cartoon - it should literally be burned into your mind :)