Words produce effects on your tongue and in your mind. They reveal the nimbleness of your vocabulary and reflect your ingenious (or inept) writing style.
Before you learned to scrawl words on paper, you learned to speak, and you developed a pattern of speech (probably from your parents). Have you listened to a two or three year old? Don't we often giggle over how they pronounce a word or structure a sentence? And as you listen to them, can't you see their little personalities pushing up through their use of language? I love it!
Like a toddler learning to put together sentences, so a new writer must learn to mold words into forms that paint images in the minds of his readers without inhibiting his personality. To do this he must play with his writing.
Here are some things I've done to help me develop my own style:
Write an entire page describing the most recent event in your life without using state of being verbs.
Write an entire page on your loved one in one syllable words.
Diagram an entire paragraph from a novel (do you know how to diagram a sentence? One of the most useful skills a person can learn).
Freefall writing. Write whatever comes to mind and let it form into a story.
Write a rhythmic poem on some humorous situation.
Write a gothic poem on some over-the-top melodramatic event you've recently witnessed. Know any drama-queens? They're great subject matter.
Sit in a coffeehouse and write a description for each person then write a fictitious scenario about each person.
Fill a page with nouns followed by action verbs. Use as many unique verbs as you can.
Back in that coffeehouse, take one person and give him a goal, a conflict to that goal, and some disaster. Play out a scene (not literally--jot it down on that notebook that's been traveling with you wherever you go).
Take another person in that coffeehouse and give him a disaster from which he just came. Describe how he feels, what he thinks, how the rest of the world sees him now since that disaster. Give him dilemmas with no good options and help him come to a risky decision on a course of action.
Now go to the park and watch the kids. Yup, they are the most reactive characters you can find. Jot down each action done and how they react. For example, Little Suzy kicks Little Tim. Little Tim screams, screws up his face, then whips around and punches little Suzy. (Nasty little boy, isn't he?)
Listen to the speech patterns of the people around you, in that coffeehouse or at the park. How do they form sentences? How do they describe things? What unique words do they use?
The list could go on and on, but I'm sure you get the picture. The more you play around with writing, the more your voice will develop, and you'll learn the most emotive and effective way to frame your sentences and paragraphs. And this will come in handy when it's time to write that novel.