You need to start by understanding the basic anatomy of the head and neck. Focus on the movement and positioning of these parts to make the nodding look natural.
As a fan of online literature, I don't have any specific sources of information, nor have I ever heard of authors who are vermilion clothed and nodding their heads. If you can provide more information about Zhu Yi nodding, I will try my best to provide you with a more accurate answer.
An arc in a story is basically a sequence of events that follow a certain pattern or have a clear beginning, middle, and end. It often involves character development or a significant plot progression.
A story arc is basically the overall structure or sequence of events in a story. It shows how the plot develops and progresses from the beginning to the end.
The arc of a story is basically the journey or development of the main characters and the plot from the beginning to the end. It includes the ups and downs, conflicts, and resolutions.
Arc Troopers are often characterized as highly skilled and elite. They're shown to be more independent - thinking than regular clones, able to adapt quickly to different situations.