One technique I've tested against watching movies and noting sequences is devising questions. Here's how I did it.
I can detect when the objective story turns in a major new direction (the drivers at roughly quarter points of the story). I looked up the signpost order for this objective story. I developed a skill to figure out the key question to be answered in the signpost climax.
So, I would develop a question sparking off each sequence, and is related to each signpost.