When I debutted to online writing, I didn't know what to "say" i.e. write. Even If I was armed with ideas, then, I was paralyzed from the neck up! The stack of reference materials was to no avail, the zest dissipated and inspiration evaporated.
What is this "voice" you're talking about, you ask? Surely it isn't the passive voice of grammar, is it? Or the voice using our human vocal cords?
I have with me a book on Creative Writing, a reference I have since relied on when I started writing online, called "Complete Idiot's Guide To Creative Writing," with Laurie E. Rozakis, Ph. D. as author. I tell ya it is so cumbersome cradling a book on my lap as I type on my keyboard.
I will quote from the darn book, A Voice In The Dark:
"According to Philip Roth, a writer's voice is 'something that begins around the back of the knees.' Voice lets us tell stories that are uniquely our own. Good writing has a sense of life that forces the reader to keep going. There's the sense that a real person wrote the text. That's voice. It's part of the writer's style."
The shy individual that I am in real life, I took on a different personality when I learned to find my "voice" when I was forced to write. It helped a lot to assume at least one pseudonym, or pen name, to find that confidence, and therefore that "voice". Call that a brash and different personality like Mr. Hyde's and therein lies your plunge to the murky waters of writing.
Once I got accustomed to that different personality, once I have, in fact , gotten used to the behaviour of the "voice", and once I have learned to call a spade as a spade, in writing, with all the guts I could muster, in contrast to the "shy, inhibited and reserved" type of an individual that I once "was", then be prepared read my write descending to pathos in poetry and ascending to a watch tower from which we can trade barbs or arrows of prosaic misfortune.
See? You now know what I mean. That's "voice" pure and simple.
For you cannot carry with you the normal speech habits attributed to what the domestic environment, you have fashioned for yourself, like a cat communicating to a cat. But caterwauling might be as close to the "voice" for what its noisy worth notwitstanding the irritation it can cause to the neighborhood.
Likened to the cat who frequently does it, you will have acquired that "voice", much more resounding with the mighty pen and keystrokes.:-)