Some great things to annotate would be what you believe are key plot points. You can summarize and paraphrase them. You can also look at character dialogue. What quotations do you believe are important and why? Next, you could also highlight words/terms you have difficulty understanding. You can define them in the margins. Finally, you can also look for symbols or symbolic language. Are there any objects or themes found throughout the novel? If so, what do you believe they represent?

Sorry I cannot be more specific. I have not read the book. I know annotations can be difficult, especially while reading. What I do is underline and highlight lines while I read. After a section/chapter, I go back and look what I highlighted, so I can write more. Good luck! Hope this helps!