Write for yourself. Talk about the things you care about. Construct an opinion on them. Take a clear position. Then, be flexible — as you learn more, your position might change.
This is what I tell myself when I sit to write. I learn (a lot) by reading what others say — but we won't go too far if we don't build an opinion of our own.
As Seth Godin would say: Don't hide. Write in public.
Then maybe, just maybe, what you write will resonate with your audience.