First, you were researching to develop a topic idea and come up with a research question. Once you have your topic narrowed down, you'll move into the next phase of research. Now, as you research, you'll start to categorize different books and articles naturally in your head. Our brains our wired to find connections, so sometimes it helps to spend time researching and then put it aside without thinking about it for a day. Your brain continues to problem solve in the background, even when you aren't conscious of it!
As you start to realize what the major sections of your paper are, try creating an outline. If text outlines are too formal for you, try thinking out of the box by creating a mind map!
Mind mapping is a great way to organize your thoughts visually. There are digital tools you can use (check out this list of 5) but it's usually more effective to create one on paper by hand. They can be used for:
Studying: Map a textbook chapter or lecture notes to better understand, remember, and make connections
Writing Papers: Map out your thoughts to generate a topic or thesis question, outline your supporting research, and find connections to help you with transitions
Presentations: Present information visually, so that the audience can see how your ideas are organized and connected
See mind mapping in action: