If you want to be a writer, write. Write and write and write. If you stop, start again. Save everything that you write. If you feel blocked, write through it until you feel your creative juices flowing again. Write. Writing is what makes a writer, nothing more and nothing less.  Ignore critics. Critics are a dime a dozen. Anybody can be a critic. Writers are priceless.  Go where the pleasure is in your writing. Go where the pain is. Write the book you would like to read. Write the book you have been trying to find but have not found. But write. And remember, there are no rules for our profession. 
Anne Rice