You're probably familiar with verbal tics - we all have them to an extent and they are part of what makes a person's speech unique. Lately, I've met a number of people in a wide variety of settings using the word yeah repeated three times in quick succession (part of a movie or TV show I've missed?) That's one example of how you can use a tic to distinguish a character. But tics in the writing itself weaken your narrative and annoy the reader.
Once you've developed your voice as a writer, consider taking a look at your writing tics. Some of it belongs there, but you may be surprised at what you don't notice along the way and what needs to go. I've been doing some revisions my first novel in order to publish it as an ebook (more on that later), and noticed a heavy reliance on "very", "really" and "actually". How heavy? 226 uses of the word "very". Well, that's embarrassing. The good news is my writing has improved since then.
Advice? Use the Find function and search your manuscript for common adjectives and adverbs. Then check your dialog tags. "Said" or "asked" only please. None of that "she retorted" nonsense. After that's done, read your manuscript out loud. Yes, the whole thing. It's invaluable. You can also put it all in another font and/or color when editing in order to spot mistakes that have become so familiar, they are hard to see. Clean up your act. Writing tics will suck the juice out of your work.