Take a look at the assignment. What information are you going to need? Think about the elements that you have to discuss.
Conduct background research. First, to help you select the topic you want to discuss if you have not decided. Second, to help you focus your topic, which will make writing easier. You want to know what information is out there, and how the topic has been already discussed.
In this background research, make note of any other terms that you see that related to your topic, this includes synonyms, technical terms, relevant theories, and historical names.
Think about what you found in the first steps two steps and develop keywords for each aspect of your topic. This will include keywords for each aspect of your research question or the aspects of the topic that you need to address. Think of broader and narrower terms, synonyms, historical terms, and possible cultural terminology. Use the notes you made in the second step.
Conduct some searches using keywords. When searching, don't just look for results that work, but also make note of what you are seeing and what you are not seeing. This will help you modify your search. Try different combinations of your keywords. If you need help along the way make sure you contact your friendly librarian. They are experts at locating information and love to help.