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Just as each person's voice is unique, each writer has a voice of her own. She (or he) uses words in a certain way, prefers specific sorts of sentence structures, organizes in given patterns and, generally speaking, has an unique writing voice.
This is how teachers of writing spot plagiarism, even before they've run a batch of papers through a style checker. When a writer's voice suddenly changes, the teacher becomes suspicious and begins looking for the true source of the words on the page.
So how do you attain your own unique writer's voice? Write. The voice happens.
That sounds like a simplification, but it's exactly the way it works. Prolific novelist Nora Roberts once told a group of us at a writer's conference that she didn't discover her own authorial voice until she was working on her eighth novel. Really. She knows her voice now, but it's been there all along, even from Book One.
Style is different, although subtly so, and you can exercise more conscious control of your styling.
Are you overly fond of adverbs? Learn to control them, saving them only for moments when they will make your image crisper, your character more appealing, your story more direct.
Do you seek for all kinds of ways to vary words? Don't do it. Mars may also be known as "the red planet," but if I don't know that, might I not think you're writing about TWO planets when you put Mars in one sentence and "the red planet" in the next?
A conscious study of your own style is one good way to make the serious leap from "I'm thinking about it" to "I'm a writer." I commend it to you.