
#1 It’s about the audience
As my study guide from that time so delicately states:
An audience doesn't care about your pain and your suffering. They care about their own. They are human beings after all. Your pain and suffering is only useful to an audience to the extent that it can assist them in addressing their own pain and suffering. Unfortunately, taking the particular pain of one person, especially when the writer is so close to the subject matter, and turning it into a universal statement that speaks to countless people is a hard act to pull off.
There are forms of writing where it is about you (e.g. memoir), but generally speaking, you need to think about what the audience will enjoy and how you can make your ideas interesting to them. This does NOT mean you should jump on the bandwagon of whatever form or genre is popular right now. It just means that your primary purpose is to entertain, not to lecture. No one cares about your opinion until you can prove it in a good story. So, write what you know, but your experiences and interests are just a starting point. You need characters we can relate to, emotional experiences, and universal themes.

Before I was even allowed to start writing my script, I had to present a premise, a plot outline, a breakdown of how my story followed The Hero’s Journey, answers to questions about my story, and a scene-by-scene summary. At the time, this annoyed me. In hindsight, it saved me a lot of editing.
There’s an ongoing argument in the writing community about “plotters vs pantsers” and ultimately, if you spend an appropriate time editing it probably doesn’t matter too much. But if you can look at your plot outline and ensure that you have logical progressions of events, motivated characters, tension that gradually builds to breaking point etc then you’re less likely to write yourself into a scene you can’t get out of or produce a story where nothing happens.
The planning process isn’t just about knowing where you are going. It’s about identifying problems with structure, contradictions in how your imaginary world works or how your characters behave, and ensuring that you have a complete story arc and character arc.
We tend to teach school students to “plan” by giving them character profiles and having them think about the different elements of storytelling, like setting. This isn’t really a plan. I’ve posted before about using goal, stakes and obstacles as a simple way to decide what your story will be about. From there, I think it’s very useful to develop a dot point outline of what will happen in each scene of your story, then share those outlines with one another for feedback.

Premise, theme, moral, message. Lajos Egri popularised "premise" but it doesn’t really matter what word you use. The point is, a story needs a purpose. What are you trying to prove? Why should your audience care? What universal theme do you explore that gets their interest and helps them to empathise with your main character?
There’s a formula for premise that looks like this:
Value ascendant over its opposite value for a reason.
That’s a mouthful, right? To write your own premise, fill in these blanks: ___________ is better than (or defeats) _________ because ______________. In the first two spaces, you want two values that contradict each other. Good and evil. Love and hate. Honesty and corruption. The “good” value doesn’t always have to be the one that wins, but readers tend to like stories where our moral code is reinforced.
Egri lists a number of possible premises in the first chapter of his book, The Art of Dramatic Writing. If you’re struggling to come up with an idea of what to write, have a look through them and think about a story that might prove each of those lessons. If you already have an idea, answer the questions: what opposing forces are battling one another in your story? What lesson do you readers learn?

We like characters with flaws. They’re more relatable, more human. This is a well-established fact and you’ve probably already been told to let your characters fail sometimes or give them a trait that isn’t as appealing. You need to balance this with qualities that make them likeable; otherwise people won’t care what happens to them.
But it goes further than that. The flaws that you give your character should exist for a reason, they should impact his/her story, and they should be addressed by the end. In scriptwriting, everything had a formula. The formula for character arc was this:
Act One – There is a flawed Hero who sets out to achieve something
Act Two – The Hero’s flaw gets the Hero into trouble and stops the Hero from achieving their goal. Ultimately, the flaw gets the Hero into fatal trouble and the Hero is forced to address the flaw
Act Three – The Hero overcomes the flaw, freeing him/her to pursue his/her goal
Notice how it is the flaw that gets the Hero into trouble and the Hero cannot achieve their goal until the flaw has been overcome. “Fatal” trouble can be taken more metaphorically, but the idea is that it has to hurt. A lot. It should be impossible to move forward without facing the truth and some kind of self-improvement.

If you go back to your premise, you should be able to identify the two values that are “battling it out” in your story. A one-sided battle is boring and usually it’s finished quickly. Of course your reader is going to want – even expect – a particular outcome, but getting there is the fun part.
Maintaining tension is a game of “almosts”. You want your character to almost win, but not quite. The you want them to almost lose, but not quite. Harry Potter didn’t destroy Voldemort in the first book, but he stopped Voldemort from getting the stone, and that was enough to keep a generation reading through the sequels. Harry almost died in the battle, which also helps.
Look at your plot outline and see where the power shifts. If your premise is about proving that good is greater than evil (because ________), then there should be alternating beats where good is winning, evil is winning, good is winning again. If you think about your character’s goal, it should look like they will achieve it, then that they will fail, then that they might achieve it again. And of course, to generate tension, the stakes can be getting higher each time, the battles should be getting harder, and the time can be running out.
As a rule, writers hate rules, and of course there are always exceptions. But I’ve found these 5 principles to be good rules – the kind that give you something to work with, rather than constraining you. I hope you find them helpful.