"Writing is a way of talking without being interrupted." - Jules Renard
Maybe the best advice I can give is … don’t be afraid to write what you want to write. Don’t decide to write a serial killer book because they’re selling, or steer clear of a subject some readers might find objectionable. Once you’ve decided on the book you want to write, work intensely until it’s the best book it can be. Don’t be afraid to listen to criticism, but pick your critics carefully.