1 Watch and learn
It is essential to view as many films as possible, good and bad. The classics are not top of the best-ever lists for nothing, and it is difficult to be original when you don’t know what went before. Working out the structural kink in say Memento or the emotional punch of something like It’s a Wonderful Life cannot fail to inspire your own thought process.
2 Don’t show off
European writers in particular try to make their work look complex and clever. The major skill in screenwriting is making the multifaceted seem simple and accessible. Look at Shrek.
3 Structure
Every script has to have a beginning, middle and an end. Once you remember this you can play with it (see Pulp Fiction, where Tarantino started in the middle, went to the end and then back to the start).
4 The story must have a point
Like it or not, the story has to be about something, with a goal at the end, or it lacks interest (Bertolucci's The Sheltering Sky looked great, but had no real premise). If you can’t describe your story by saying “once upon a time . . .” then maybe there’s no story. A conventional plot will follow someone who has had their status quo interrupted; the drama comes from that person trying to redress the balance.
5 If it’s not 90 minutes then there must be a good reason
Generally speaking, one page of screenplay will take a minute of on-screen time. A movie should be 90 minutes. If your script is over 100 pages there had better be a good reason for it (Ghandi was deserving of three hours; many others are not). Commercially, if you go much above 100 minutes the cinemas will lose one showing a day.
6 Choose your protagonist
Movies should have a protagonist. This can be more than one person (Crash), or even an inanimate object or a place (Fargo). They do not always have to be sympathetic, but they do have to be intriguing.
7 Make an impression
There has to be some suspension of disbelief for a film to work. This is easier for some stories than others but if in doubt, think of Groundhog Day. This was a truly preposterous premise, but logical at every step.
8 Avoid being linear
Movies benefit from having at least two contributory subplots to help vary tone and pace.
9 Be original
These are general guidelines. But you must be true to yourself and your vision. Don’t simply copy others. Good movies stand out because they dare to be different, whether it be the tongue in cheek tone of The Big Lebowski or the reimagining of the Brit gangster flick in Lock Stock and Two Smoking Barrels.
10 You’ve either got it or you haven’t
Talent that is. All the courses and screenwriting gurus in the world will not help you if you don’t have aptitude. There is a knack to writing dialogue that doesn’t feel wooden when spoken. So, happy writing!