To help us along the way there are some structural guidelines and practices to take into account. The Three-act structure is widely taught in screenwriting books and courses for beginners. However, John Truby has a different view and outlines in detail and length "Why 3-Acts Will Kill Your Writing." The fundamental problem is that the structure isn't at all about character.
How are we supposed to structure character growth?
Here is where a number of useful and insightful character development structure guidelines come into play. For instance, John Truby has his 22 Steps in The Anatomy of Story - Joseph Campbell developed The Hero's Journey - others have their own ways, steps and points but will require some research and experimentation to see which one fits your screenwriter feet.
I hadn't heard of this one until recently after discovering The Script Lab (where have I been!) and found an interesting article there regarding 'The Sequence' way to view films and write screenplays.
The 'eight-sequence structure' approach was developed by Frank Daniel, a Czech film director, producer and screenwriter. In essence, the script is broken up into eight 10-15 minute sequences and each serve as mini-movies with their own compressed three-act structure and carry an overall three act structure.
With The Script Lab's personal touch - it's the most straightforward and helpful screenplay structure plan I have seen. If you haven't heard of it before I recommend going over to the article and having a look.
Then the next time you watch a film, keep the eight-sequence structure and these 'mini-movie' sequences in mind and it will help you to write and visualise your next screenplay.
What's the Deal?
Ultimately it comes down to what you are comfortable with using and developing into. It doesn't hurt to refer to one or alternatively just to keep in mind for now. But at some point when your writing develops and you crave a tighter structure then these guidelines are here to help steer you and your main character and screenplay in the right direction.
It’s easy for a beginner to be intimidated by structure and the different ways of approaching it because everything on screenwriting is being learnt all at once. It takes time to see the various elements that a screenplay comprises of but it's just a matter of re-writing, researching the craft and continual learning.
However, a mistake would be to try and force a story into a rigid structure and compromise creativity, exploration and enjoyment, unless you know what you are doing.
"Screenplays are structure."
- William Goldman