When I wrote the book I had a lot of inspiration - I visualized certain actresses and actors in the various roles of my characters. I also listened to a lot of music and certain songs resonated with me for certain chapters. In particular, Chapter 1 has always been correlated to U2's song, All I Want Is You.
The pacing of the chapter I got down to actual time marks. The first few minutes of the song I visualized Peter flying in over the Golden Gate bridge on his way home from Hong Kong while Grace drove to the airport to surprise him by picking him up.
Here are some additional time marks in the song:
3:00 mark: Grace walks into the airport
3:45 mark: Grace sees the younger woman come into the Arrival Waiting Area
4:10 mark: Peter exits through the Arrival Doors
4:30 mark: Grace runs away