Only download software from a trusted source. The allure of free software can be quite seductive, but you might end up paying in other ways. Many developers, such as those who produce file-sharing programs, make their money by bundling adware or spyware with free products. Warn users to be particularly wary of "fun" freebies such as screensavers, emoticons, and games.

Before downloading anything from the Internet, it's crucial to scrutinize the Web site's privacy policy (usually located near the bottom of the page), keeping an eye out for questionable or suspicious words and phrases -- such as "banner ads" and "third-party software" -- that might indicate the presence of adware or spyware.