The thing that most of us want to be in our writing is unique. It doesn’t have to be out in left field or pie in the sky to be unique.
We all have our own voice and our own way of putting sentences together. You need to develop that in your characters. Each one has their own voice, their own phraseology.
Under it all there is also your voice as a writer.
That is the uniqueness you need to develop as you write more and more. The only way to develop that is to write. A lot.
When you pick a story to write or it picks you, try different ways of expressing that story. Maybe set it in the future or the past where the language might be slightly different that today.
Take one of the characters and make them talk or act in the manner of a time past. We have all met people who use words from other languages to get their point across or just do it all the time.
Do you know how you catch a unique rabbit?
Unique up on him.
And that is also how you become unique. U niique up on it.