What are the best techniques to write a genuinely natural script?

Some of them can be- Keep the main plot simple. If there is too much going on, the general population won’t get it. Think accessibility, not complexity. Have a strong start; to capture and hold the audience’s attention. The structure is usually beginning, middle, and end, but that doesn’t mean they have to be revealed in that order. Flash backs and flash forwards can help to keep the audience engaged. Make sure you have an overall goal or point to your story. There needs to be a reason for telling the story.

It depends on the genre you are writing, and on the style you want to practice or concentrate in.