The best defense against spyware and other unwanted technologies is to prevent them from getting on your computer in the first place. Awareness is the best approach to protect yourself online, so staying up-to-date on current threats and safe surfing practices is essential.  Here are some steps you can take to stay safe while still getting the most from the Internet and software programs.
Keep security on your computer up to date.

• Update security patches:
• Many malicious spyware developers exploit known security holes in essential software, such as operating systems and browsers.  Update essential software frequently. Automate the process if your vendor offers the option.
• Security and privacy settings in Internet browsers:
• Many Internet browsers have security and privacy settings that you can adjust to determine how much—or how little—information you are willing to accept from a Web site.  Check the documentation or help file on your Internet browser to determine how to adjust these settings to appropriate levels. See GetNetWise.org for detailed  instructions.

Download programs only from Web sites you trust.

• If you are not sure whether to trust a program you are considering downloading, ask a knowledgeable friend or enter the name of the program into your favorite search engine to see if anyone else has reported that it contains spyware or other potentially unwanted technologies.
• Look carefully at the address of the site you are visiting to make sure it is not an obvious spoof.
• Be particularly suspicious of programs you see advertised on unrelated Web sites. If a maker of a screensaver, “smiley” inserter, or other program heavily promotes its purportedly-free product, the product may include extra software you do not want.

Beware the fine print: Read all security warnings, license agreements, privacy statements, and “opt-in” notices with any software you download.

• Whenever you install something on your computer, make sure you carefully read all disclosures, including the license agreement and privacy statement. Sometimes important information such as aggressive installs or the inclusion of unwanted software in a given software installation is documented, but it may be found only in the EULA. The fine print may be the only place consumers can find notice of potentially unwanted technologies.  Unfortunately, careful consumers must read all the fine print.
• When given the choice of opting into something, make sure you understand fully to what you are agreeing.
• If you have doubts about the legitimacy of the software, do not install it, or go to a trusted source to find more information about the software.  To be safe, you should never install software if you are uncertain about it.

Don’t be tricked into clicking: You don’t have to click “OK,” “Agree,” or “Cancel” to close a window.

• If you want to close a window or dialog box, consider the options provided by your operating system or Web browser, such as closing the window with the ‘x’ mark in the upper corner or typing Alt+F4 in Microsoft Windows.
• Pay attention when closing windows; some dialog boxes may have a prominent statement that says, “Click here to close window,” then in less prominent text adds, “and install software.”
  

Be especially careful with certain types of “free” programs.  

• Many file sharing applications are bundled with other, potentially unwanted software.
• Similarly, screen savers, cursor enhancements, wallpaper bundles, “smiley” inserters and any other software promoted aggressively often include extra software you did not request and aren’t expecting. Be sure you clearly understand all of the software packaged with those programs.

Use available tools to detect and delete spyware.

• There are a number of security tools available from a variety of vendors that can help you identify spyware, stop the installation of it on your PC, and/or remove it.
• Anti-spyware and Anti-virus software:
• There are a number of programs (available both free and for a fee) from reputable vendors that can help detect spyware, prevent spyware from being installed on your PC, and/or remove spyware if it is installed. (Some programs can be removed through “Add/Remove programs” or other standard operating system features.) Note that some software that claims to be an anti-spyware tool is actually adware or other potentially unwanted software in disguise. For this reason, you should read reviews to be sure any anti-spyware software you download is from a reputable publisher.
• Personal firewall:
• Installing and using a firewall provides a helpful defense against remote installation of spyware by hackers.
  

http://www.antispywarecoalition.org