Do not be tricked by messages from different programs on the screen prompting to scan your computer. Know the name of your installed Anti-Virus software (AVG, Symantec/Norton, McAfee, Kaspersky, Sophos, Webroot, etc.)
2. Do not click on ads that you see on websites
Often, a website that you trust can be compromised to display messages to the side (or even pop up) that tell you that your computer is running slow or that you could be infected with SpyWare. Clicking on these links could result in AdWare, Fake Anti-Virus programs or other types of MalWare being installed on your computer.
3. Try to avoid installing "special" viewers in order to play certain videos that you find online
Most videos require Adobe Flash Player (www.adobe.com), Adobe ShockWave Player (www.adobe.com), Java (www.java.com) or Microsoft Silverlight (www.microsoft.com) to view them. If you are prompted to install another viewer or to update one of these viewers, go directly to the publisher's site to get the installation/update (do not allow the video to install it.
4. Remember "Nothing is Free"
Everything has a price. If you are downloading free software or digital content (music, videos, movies,…), be sure to scan it with your Anti-Virus software before attempting to install/play it. If an installation is required, please read each screen before accepting wwhat is being requested (many times, you are agreeing to receive ads for daily deals, share your personal information or even give control of your Internet browsing to additional programs that will also be installed).
5. Use a reputable source to acquire software/content
Purchase your security and performance tuning software from a retailer that you trust, consult with a professional and see what they recommend or do some research and see what objective people are saying.
6. Do not be extorted by fake Anti-Virus programs
There are some so-called "free" security scans out there that have been know to block access to all of your files unless you pay to "activate" their premium features. Do not pay a "ransom to get your files back (are you really comfortable giving them your credit card information?).