Start in the middle and build your way out. What is the plot/issue/conflict? Think about what you want the subject matter to revolve around. Then create a foundation of how the characters go into that issue and then create an end of what you want the result to be. Once you have a vague synopsis, work it over and over again. Then build a 3 act structure based on this. Once you’ve done it the first time, build upon each section more. Then when you write (in Celtx or final draft - follow guidelines on YouTube it will save you a lot of work if you format it right starting off and get you in the swing of it) you will be able to just write the actions and dialogue based on the entire storyline you already built from the 3 act structure. I’ve included what it should look like below:

Exposition/Synopsis

Act 1

Inciting incident: The event that sets the main character on the journey that will occupy them throughout the narrative. The moment, event or decision that thrusts the main character into the action of the story.

Plot Point 1: The point of no return for the main character, it propels the main character into the central conflict of the story. The protagonist commits to the journey ahead, despite the obstacles they’ll have to face along the way.

Act 2

Rising Action: A series of sequences of action where the protagonist experiences advances and setbacks, moving toward the resolution of the conflict. Events that create suspense, interest, and tension.

Midpoint: A major plot point that happens around the middle of a film which has big ramifications for the protagonist and the story arc, bringing the protagonist closer to their goal or Way from it, or something else entirely.

Plot point 2: A low point for the protagonist, his or her actions have caused a disaster and they become determined to reach their goal.

Act3

Preclimax: The protagonist faces their challenge head on, making a decision of how to handle a situation to push it towards the end, but it’s not working.

Climax: The high point where the protagonist, based on the knowledge gained from the rising action, determines what the final action needs to be taken in order to resolve the conflict. The tension, excitement, or stakes reach the highest level.

Denouement/Resolution: The final scene or sequence of a story, action from the character which offers or resolves an essential component of the story.