There are a gazillion blogs out there that are all to eager to tell you how to write, but I am not one of them.
My philosophy boils down to: just do it.
Remember, 50 Shades of Grey was a mega fad, despite the rather unnerving tie worn by Mr Grey in the first chapter. Obviously, the world can be forgiving.
So who cares about rules? Just write, rewrite, edit, and nitpick, then let it out into the wild. Maybe something will happen, maybe not. The important part is creating something that you enjoy.