Is there something (a theme, a thread) in the work that appeals to you, moves you, frustrates you? Find that focus and then begin the research process. Depending on your choice, there could be a number of themes. Begin to see what’s out there using either the library online databases (EBSCO, Proquest, etc.) or print material like books or periodicals from the local library. You may not use general internet sources.
Develop points related to your focus or angle. Think about your angle: what approach are you going to take? like to see you think hard about possible approaches to the novel, what interested you, how you might use sources, etc.
Were there parts of your novel that you relate to on a personal level? Were there characters that you have a particularly strong feeling about? What theme (or themes) do you see?