To write Treatments for Television well, you can read my blog here. My work with writers via my script consultancy is all about developing the idea and then writing the documents that show the creative and commercial aspects of the story to their best advantage. Writers need to know how to write Treatments, Series Outlines and how to produce a cracking Pilot episode. So, is there a set way? Some would say no, but I would say writing stories for Television Drama requires a certain process. You need to be both creative but also present your series narrative commercially so that Producers find it easy to read and it answers their key questions about the series as a whole.
How to write a TV series outline is a tricky skill to get right.