Who will be sitting in it, and what you need them to leave with. That is the whole brief. She will take it from there.
Anything you already know is enough to start.
She reads every one of these herself, so allow a couple of days.
Class sets, church libraries, or a book table at your event.
Interviews, podcasts, and requests for her bio or headshots.
If one of the books met you somewhere, she would like to know.
Seminar dates, new titles, and the occasional Gethel sighting.
Grief; and Gethel, for when the room needs to laugh before it can listen.