It's not just the layout of a script that's important. You need to think about characters, plot and dialogue.
In a short script, it's best to limit the number of main characters. Too many characters can be confusing and doesn't give you time to let them develop. Stick to fewer than four.
Your characters should come to life. This is achieved through dialogue.
Usually a play has a conflict, crisis or problem at its centre that needs to be resolved. The characters have to face up to this problem and it is this that makes the play interesting.
The problem at the heart of the play does not need to be particularly unusual or exciting in itself. You could write a short script centred around a number of personal themes, for example:
The success of the plot depends on how well it is handled.
You also need to think about how easy it will be to present the plot convincingly on stage. Plots involving spaceships landing, for example, could lead to serious difficulties.
Good dialogue is central to convincing drama. To make it sound realistic you need to read it out loud to hear what it sounds like.
You also need to think about your characters to know how they would speak. Ask yourself: