Preparation is often the most difficult part of your search for information. If you tackle this properly, you will benefit greatly from the rest of the search process. That is why it is important to have a clear idea of exactly what you want to know before you start searching.
First gather your bearings on the subject. Then you formulate a clear main question and possibly several sub questions. To answer these, you draw up search questions. Only when these questions are clear can you determine concrete search terms with which you can search more quickly, efficiently, and purposefully!