And there's the matter of pen ink.
Anyway, I'm signing up for a course on writing. A few people seem to like my writing style so I figure there's a market out there for it (though I write primary for myself in most cases) but the matter is actually making a coherent plot which is both believable and exciting. Characterization is probably the hardest bit of all. When making characters, the audience has to be able to identify with at least one of them throughout the story, and the others have to be memorable, which is a difficult feat to accomplish if your story has 20+ characters. One of the ways to get around this is to make all of your characters physically or mentally different. some films take this premise to an extreme and create contrasting characters, such as lunatics, phobia-ridden men and such like. While it helps in the short-term, after the film, you may be left wondering : "Wait, did X have a phobia, or was that Y? Was that phobia based on Z?"
In any case, plotting is probably the second-hardest thing to do. Whilst there are good books you can pick up entirely about plotting (The man with a Thousand Faces) which talks of the Hero's Journey model, applying all of these suggested ideas to your story may not help it be original in the short-term. As is wisely stated in these books, they act merely as guidelines. One of my books doesn't follow the model much, though most others do. My fanfictions don't really follow the model at all.
Isn't that what makes writing fun though? The constant dillemas your character gets into, how they get out of them, who helps them along the way and suchlike. Think of it as some sort of obstacle in their life, and it will be more enjoyable than thinking "I have to make another character go through a Hero's Journey?" - in fact, tie it up with a recent, relevant event. Give it a timeframe. Write what you want to read, to remind yourself of why it was written. Remember, all stories have a purpose, and I'm returning to my purpose.