But though you shouldn’t consciously work on your voice as you write, there is a way to encourage it when you get to the self-editing stage. Start by rereading a short story, scene, or chapter as if you were reading it for the first time (rather as you would read in self-editing for proportion).
Whenever you come to a sentence or phrase that gives you a little jab of pleasure, that makes you say, “Ah, yes,” that sings — highlight that passage in a color you like (we use yellow) or underline it. Then go through and read aloud all the sentences you highlighted or underlined. Don’t analyze them for the moment, just try to absorb their rhythm or fullness or simplicity or freshness or whatever made them sing to you.
What you’ve been reading aloud will represent, for now, your voice at its most effective. And making yourself conscious of it in this mechanical way will strengthen it as you continue your work.
Listening carefully for any little changes you’re inclined to make while reading aloud. More often than not, those changes will be in the direction of your natural voice. If you do this exercise often enough, you will develop a sensitivity to your own voice that will gently encourage the development of the confidence and distinction you’re after.