I have a board for a memoir WIP which is a way to keep it active as a project (and something others can peek into the themes of) even when I am not writing.
Here's what I pin.
Comparable titles. Images of people who remind me of characters. Expressions and sayings that capture major themes. Images that capture what it feels like to be writing the book.
I have pinned news items and fashion pictures that would be of interest to my subject (my best friend, who's deceased).
I have pins of settings in the story, and figures she liked and things she'd be interested in today.
In this way, the project is alive. The subject is alive. The whole thing can be interacted with, now, before it has been published.
And, the transmedia storytelling is taking place right now.