I don't know much about the music business, but for just general advice for someone trying to create things, as simple as this sounds, I think the best thing you can do is constantly try to improve upon your work. Always focus on that first and foremost, and leave everything else (marketing, image) completely secondary. Obviously, easier said than done when you're trying to make a living, but if you can move along those lines and earnestly try to make things that you really enjoy it can only benefit you in the long run.