The first step in picking a topic is to brainstorm by asking yourself a few questions. What do you already know about this topic from your course readings? Are there similar ideas you might want to explore? What are the key concepts that you're interested in pursuing?
Once you've spent a bit of time answering these questions, you can take the concepts you've identified and use the keywords and phrases to start searching for information. Keep in mind that you'll need to build a base of knowledge before you can write effectively.
See the Database Search Strategies box on this page for more help with keyword searching!