A manual for writers of research papers, theses, and dissertations, 7th edition - Kate L. Turabian 2007

Take notes relevant to your question and working hypothesis
Engaging sources
Part I. Research and writing: from planning to production

To make your notes most useful, record not just the facts that you think you can use as evidence, but data that help you explain those facts and their relationship to your claim. You can create a notes template to help you remember to look for several different kinds of information (see 4.2.1).

The first three items are directly relevant to your working hypothesis:

reasons that support your hypothesis or suggest a new one

evidence that supports your reasons

views that undermine or even contradict your hypothesis

Do not limit your notes to supporting data. You will need to respond to data that qualify or even contradict your hypothesis when you make your case in support of it (see 5.4.3).

These next items might not support or challenge your hypothesis, but they may help you explain its context or simply make your report more readable:

historical background of your question, what authorities have said about it, particularly earlier research (see 6.2.2 and 10.1.1)

historical or contemporary context that explains the importance of your question

important definitions and principles of analysis

analogies, comparisons, and anecdotes that might not directly support your hypothesis but do explain or illustrate complicated issues or simply make your analysis more interesting

strikingly original language relevant to your topic