|Stanislavski. Image the property of owner.|
For me, developing the main idea is my starting point, so I like having a fix on it before I start plotting. If I can distill my story's main idea down to twenty-seven or so words, about the length of a logline, I've got my baseline for moving forward quickly with plotting.
Logline Versus Premise? - They are two different animals, and if created well, they work as complements. That said, there's tons of blogs about the difference between the two, which is not the focus of this post, so happy Googling.
I bypass premise writing and instead write a logline for my novel. The reason is simple. If I can clearly explain my novel's main idea to myself, I can then easily expand my plot in a way that saves me huge amounts of time.
Another reason I write a logline is that it contains the audience hook, which is broader and more implicit in a premise, making it unwieldy to explain to others. In this busy world, I prefer the logline, which I can easily learn and memorize and belt out in an elevator, subway, or busy restaurant. Anywhere.
If there is one dude I love to learn from, it's D4Darious, or Darious Britt. He's got a great YouTube video on loglines and how to write them (link provided below).