"I'm having trouble finding my voice," she said. "My writer's voice."
"Um," I said. "You don't need to find your writer's voice. What you need to find is your POV character's voice. Figure that out and the rest falls into place."
I don't know if this is good advice. But it works for me. It's sorta self-evident for first person narratives. But even third-person narratives - the narrator isn't (shouldn't be) the writer. The narrator is the person telling the story, and that person has its own point of view. It may be more or less supportive or critical of the POV character. But the narrator is always already a character in the story, albeit often an invisible one.
Figure out the character's voice. Figure out what the narrator's voice is from that, keeping in mind that the narrator is a person who finds the POV character a person of interest for some reason. (This is important - a disinterested narrator generates a boring narrative.)
And then, lastly, when the POV character or the narrator tell you something, listen.
What say you, good people? How do you find your writer's voice?