Read the assignment instructions carefully, multiple times. Focus on assignment guidelines - how long does it need to be, are there specific sources required, what style format is required (APA? MLA?) and of course, when is it due?
State your research idea in a complete sentence. This will give you a sense of key terms and the logic that strings them together. Identify key terms and brainstorm synonyms. Use AND, OR, or NOT to create a simple search strategy. Example: cloud computing and privacy and workplace. Word order matters: place your main topic at the beginning of your search strategy.
A number of preliminary test searches in a variety of databases and sources will show you what key terms work and which ones do not. Keep a written account of successful terms or phrases that return good hits. Always have a strategy ready to narrow search results or broaden them. Remember to think about filters or limiters, such as limiting results by a range of publication dates, by type of publication, or sorting by publication date, so tthat he most recently published articles will display at the top of your search results.
The purpose of the research will often lead to the source to use to find related, applicable information. Statistics might be best searched in a Google search limited to "site: gov" to find governmental web sites about that topic. Use subject-specific databases (Medline for health topics for example) and, again, try many databases and many terms.
This is a critical step, and is covered more completely in "Get Organized, Stay Organized."