Because of my designer background I think visually and need to draw diagrams to make sense of things, I don’t know how other writers work, maybe lists? This visual way works well for me. I used a large A2 sheet of paper and drew a diagram with my characters and their relationship to my protagonist. Then I drew out the plot/motivation and chopped the story up into 3 acts: 1st quarter, middle two quarters and last quarter. This helped to pace the story, introducing the reader to the characters and setting, then getting the reader deeply involved with the characters, then lastly the climax of the book as it reaches the end. It helped to work out the arc of the book. I then drew a section on settings this helped me to plan where the story would take place and the journey (literally) it would take. The last section I added was other characters that would need to be in the book to anchor the story to places and allow me to expand the story in what ever way I wanted as I wrote. Some characters appeared as I wrote without being initially being planned in.