For more tips, see
Zotero is a free research tool. Use it to:
We recommend Zotero for Firefox, to work directly from your web browser. [also available for Chrome, Safari, and IE]
The Jacobson Center for Writing, Teaching and Learning offers individual help with writing and also this useful guide:
Writing Papers: A Handbook for Students at Smith College
Read "Acknowledging and Documenting Your Sources" starting on page 57 (pg. 67 in pdf file).