There is only one circumstance in which you ought to use “literally” to modify what you are saying: When what you are about to say is so often used only metaphorically, that you don’t wish anyone to assume you are speaking metaphorically.
e.g. “I was literally as high as a kite when I was up in that tree, trying to get my kite.”
In all other circumstances, if you literally mean what you are saying, go ahead and just say it.
e.g. “This is the best post I’ve ever read on any subject.”
Go ahead. Say it.