What's on your mind to develop an idea for that assignment? "Who, What, When, Where, and How."
These are the basics for writing school papers--and they work very easily in planning a thesis too. They are the backbone of good journalism too. They help students prepare notes for public speaking, they are useful for research, and they keep you focused.
"Who" is anyone relevant to your subject or idea. If you need citations, the better individuals in a paper or assignment are ones who are experts or noted in the field that you're discussing. Credentials count here, both in a job title as well as academic pedigree (Ph.D. or M.A. as possible. You can also show where they work; a quality source can be referenced by an academic or other professional organizational connection.) The "Who" of your assignment or paper shows the significance of someone who comments or validates ideas that are connected with your thesis and the subject of your paper.
"What" is part of the thesis: it tells the basic material and structure of the idea itself that you are presenting. The "What" of a paper or assignment shows the reader or audience the background information and properties.
"When" has a lot of flexibility. Human nature being what it is, the topic you're writing or addressing will have a repeated pattern of occurrence over a sequence of time. People tend to do the same thing(s) again and again, and that's what makes literature a snapshot of historical perspectives. Whatever your topic or subject, it's probably come to the attention of someone over a period of decades or centuries. "When else" did your topic or thesis come to world or society's attention?
One of the ideas I used as an example here was/are the problems with food safety and preparation for the general public. I went back to the early 1900s and Upton Sinclair's book "The Jungle," about the meat-packing industry in Chicago. I then connected that to the changes in policies that allowed food additives and preservatives in the 1930s...to the outbreaks of food poisoning throughout the '80s-'90s ...and then on to the recalls of millions of pounds of meats and Mad Cow disease. It all keeps on going over time: that's "When" it matters.
"Where" is just as easy, especially because we have become a global marketplace. Whatever your topic, it just doesn't happen here in your local environment: it's likely to have manifested in other countries on other continents. Look at the upgrades and changes to technology, and you can see more easily how this happens. The food industry is still a great example: we're not the only nation experiencing obesity and the problems that come from fast-food chains. Just ask the other countries who are finding that their people are showing a tremendous rise in size as well as heart disease.
"How" is part of your thesis as well: it's showing the details; the facts, the small key components of information that validate and confirm the idea that you're presenting. This is where the experience and importance of "Who" comes in: a person who is a credible source has more "impact" on the subject because they are an authority, or at least, someone of quality.