You can’t do everything the first time. You have to build yourself up gradually.
Screenwriting software is your personal trainer. It will help you get going by putting your scene headings in caps for you and indenting your dialogue the proper amount.
But eventually you have to build your own understanding of when to use terms like (V.O.) and SUPER. This understanding comes from reading formatting books, modern scripts, and screenwriting sites. I say modern scripts because a lot of these issues change with time.
Once you understand all your tools, you have to navigate the more advanced gray areas where not all writers agree. Issues like putting a scene heading in the middle of a sentence. Some of these issues have to be dealt with on a case by case basis. I recommend joining a forum to discuss these cases.
Just don’t overtrain. It’s a great way to kill your desire to write.
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