You're exactly right, but as ksteem pointed out in another comment, it's about consistency and practice. I mean, take what you do, creating your self-portraits. I'm sure you practised, experimented and made many errors that you have rectified to leave you with your images. I know you have. So, that's the key. Whatever works I suppose, and through doing it we learn what those things are.
I'm sure you have lovely hair, so don't tempt fate by saying splitting hairs, that's the last thing you need. :)