A beat is the smallest change that deserves its own frame. Location change, subject change, or intention change. A new line of dialogue with the same camera is usually not a beat.
First-pass boarding is beat-finding, not drawing. How to make a storyboard starts here on purpose: teams that draw first re-board once the shot list appears.
How to mark beats in a script
Read until something in the picture must change. Put a slash. That slash is a frame. Coverage (master / over / close-up of the same beat) is extra frames for the edit, not extra beats in the story.
Beats vs coverage
A two-page dialogue scene may be four beats and twelve setups. Both numbers belong on the board. Coverage.
- Story beats answer “what happens”
- Coverage answers “how we can cut it”