Come up with lots of ideas of what you want to happen in the play, movie, or TV show. Create the premise and purpose of that story. What are the circumstances and what are the goals of the stories and main characters involved?
Your characters will drive the action on the stage or screen, so make sure you make them interesting and innovative. It may not be necessary for you to develop all of the characters right away, but some writers need to have everything set out before they can begin working. Find your method and work with it.
Edit yourself. Continually revise your writing, and, if possible, show the script to a friend or adviser who has writing experience and can critique and improve the script as needed. You may also write your script in various ways, introducing people and even in brackets telling the reader what is happening that the narrator is not reading. I.E.) Niranjan walks off the stage or Yamuna closes the door behind him.