Keep your eyes on the stage throughout the show so as to maintain actor safety. Cues or no cues, the ASM is there to look at the stage from his/her vantage point, as the calling SM often sees the show from a different perspective.
Make a calling script and listen to the call of the show so that you can back up the Stage Manager, if necessary.
Make sure the blocking book is completely up to date, representing what actually happens onstage, not what happened back in rehearsal.
Take line notes for every performance, so that the calling SM does not have to, while they are calling the show.
If your SM agrees, take notes from him/her, and so as to get a jump on the performance report. This is especially helpful in a scenario when the SM has a lot of cues to call and little time to write notes.
By all means, find ways to remain engaged with the performance and to know more about the show you are doing! Stay busy with show related tasks, even if you are simply solving potential challenges in your head.
But above all, look at the stage!
Hello SM friends!
I couldn't find another topic about this, so I thought I'd start my own.
How do you keep yourself busy backstage as an ASM on a show with few cues? It's a fairly long run.