You arrive at the airport and board the plane. In your seat, while people are filing on and everyone around you is tapping on their phone, you pull out your notebook to start recording the beginning of the trip. The flight will give you perspective and time to think. Things occur to you when you're 30,000 feet up in the air, things you want to do, things you want to see, projects you want to work on. Once you arrive, you'll alternate thoughts with sketches, bringing home pieces of the trip as seen only by you.
For some, this is a slim, easily packable book that you fill quickly and buy another. For others it is a fat, leather cover packed with all manner of things, growing over time with each new destination.