How to blog as a new fiction writer?

I've just started my new blog. I am a fiction writer and have read that blogging is an excellent way to market.

But I'm curious. What do I blog? Do I post my story online? I was thinking that it might be smart to put a description of my book along with my prologue on my blog to start and see what kind of feedback I get, such as if people like the overall idea of my book.

Then, instead of posting the whole story on my blog (once it's finished) I'll post little parts of each chapter that way if my book gets published, it'll still be desirable to read.

Does this sound like a good plan for my blog? Or would you recommend I blog a little different? I just started so how can I build a fanbase for my book? I'm not nearly finished it but I've read that marketing is extremely important at the beginning. Also, say I was to post bits of my story online, would people steal the idea? It seems a little strange but the thought makes me nervous.

I apologize for all of the questions and I appreciate you taking time to answer them. Thank you! Xoxo
-Meg

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