Most important? Write like you. Who can do that better? Find your way of expressing your way.
It's hard at first. New writers often want to write like the writers they love. They mimic them in various ways. That's OK. Writers will get past trying to be the writers they admire if they keep writing. You can't be those writers. Only they can so...
Write what you love. Write what you love to read and watch. But also write from your passions, things that you care about, people, your life. You are unique and you will write in a way that is like no one else.
Put your quirks into your writing. The details of you will help shape the details in your writing.
Keep experimenting, evolving, trying new things that are just beyond your abilities. Being you doesn't mean you write one way. It means you write with all the complexity that is you. And you grow and change as a writer. Embrace that.
Tell the stories that you have to tell, that call to you at a particular moment in time. They're the ones you have to find a way to get on the page or screen or whatever. They're the ones that are most likely to teach you how to write them and others like them.
Writing is a journey. It's a life-long journey and the journey is what's most important. You may never find the perfect you or the perfect story but the search--frustrating, rewarding, infuriating, troubling, engaging--is one of the things that puts life in life.