Keep your operating system updated.
Use the automatic update feature. Even if you don’t want it to automatically update your system, have it download & notify you the updates are available, then install the updates at your earliest convenience. Don’t wait too long, when malware writers find out about a flaw they can be very quick to exploit it.
Keep your browser(s) updated
If you use Internet Explorer, this is done when the rest of the Windows operating system is updated.
If you use Firefox, it will tell you when an update is available and prompt you to download it. You can also check for updates anytime you want to by clicking Help and then Check for updates...
Adjust your Web browser's security settings or use a more secure Web browser. Adjust your browser preferences to limit pop-up windows and cookies. Certain types of cookies are sometimes considered spyware because they reveal what web pages you have visited. You can adjust your privacy setting to only allow cookies for the web site you are visiting.
Install and keep updated: a firewall, anti-virus, anti-malware
And when it’s time, RENEW your subscriptions. They can't keep you protected if they aren't up-to-date.
Consider a "suite" of software – a suite is individual application programs that are sold together as a group often sharing a more-or-less common user interface. They also often have features that stand alone programs and some can be used on up to 3 computers. But you should have at least 1Gb of memory otherwise you’ll get slow performance.
Windows XP & Vista have a built in firewall – use it!
Generally, free software doesn’t perform as well as pay-for programs but they are worth considering as supplementary protection. Use pay-for programs for realtime protection (majority of free software only do scans of your computer, not realtime protection), and then use the freeware periodically to check for malware the other may have missed. Use caution downloading freeware: for instance some so-called anti-spyware is actually spyware. Do some research with you favorite search engine.
Get a spam filter only if you’re using your ISP filter and you are still getting too much spam.
Keep ALL your applications updated
This includes all the add on programs you’ve downloaded like iTunes, Quicktime, Acrobat Reader, Java… these have all at one point or another been found to have vulnerabilities.
Turn off your computer.
If you have a “always on” connection like a cable modem or DSL, this will reduce the chance a malicious remote computer will access it. And it’ll save energy.
Watch what you download
Only use well-known manufacturers or trusted sites (download.com, snapfiles.com, tucows.com)
Use caution when clicking on agreements while you are using a Web-based service. Read the agreements before clicking them. Most people do not take the time to read these agreements: you may be agreeing to let spyware be loaded on your PC. If you're not sure whether to trust a program you are considering downloading, enter the name of the program in your favorite search engine to see if anyone else has reported that it contains spyware. Definitely avoid some of the known spyware carriers, such as: CoolWebSearch, Kazaa, Grokster, Snood, Weatherbug
Beware of peer-to-peer file-sharing services. Many of the most popular services include spyware in their installation procedures. Never download an executable file from a P2P. In general, you should only download executable files from known vendors or trusted sites.
Don’t click on hyperlinks or download files in emails, IM, chat rooms.
Most users infect themselves by clicking unexpected or suspicious links in e-mail, IM messages or on questionable Web sites. Links can also show one address but take you to another.
Don't follow e-mail links claiming to offer anti-spyware or anti-virus software: Like e-mail viruses, the links may serve the opposite purpose and will actually install the software it claims to be eliminating.
Use disposable email addresses to thwart spammers
Use different addresses for different purposes. Guard your primary address and use it only for trusted personal communications, use disposable ones for things like shopping – when they attract too much spam, dump it and create a new one.
Sometime look-alike sites are created that use common mistypings of popular web addresses.
Backup your data
Use external hardrives, flash drives, DVDs to backup your data regularly.
Yes, it’s a pain to change and keep track of passwords but they are a very important part of keeping your computer and your accounts safe. If your password is compromised, an intruder may obtain access to your email, your data files, your bank accounts, your personal information or your identity.
Don’t have any accounts without passwords.
Make sure the password on your administrator account and all accounts that have administrator privileges have very strong passwords.
At Northern, the person to whom an account is issued is ultimately responsible for all activity in the account.
Use credit cards when shopping one line.
The safest way to shop on the Internet is with a credit card. In the event something goes wrong, you are protected under the federal Fair Credit Billing Act. You have the right to dispute charges on your credit card, and you can withhold payments during a creditor investigation. When it has been determined that your credit was used without authorization, you are only responsible for the first $50 in charges. You are rarely asked to pay this charge.
It is recommended that you obtain one credit card that you use only for online payments to make it easier to detect wrongful credit charges.
E-commerce shopping by check leaves you vulnerable to bank fraud. And sending a cashier's check or money order doesn't give you any protection if you have problems with the purchase.
Make sure your credit card is a true credit card and not a debit card, a check card, or an ATM card. As with checks, a debit card exposes your bank account to thieves. Your checking account could be wiped out in minutes. Further, debit and ATM cards are not protected by federal law to the extent that credit cards are.
Guard your personal information.
Never respond to emails or popups requesting passwords, user names, SSNs or other personal information, no matter how official it looks. If you’re asked to call a telephone number, verify that phone number independently.
Read more about Identity Theft
Review your credit reports regularly.
Read about Protecting Yourself from Identity Theft
Don’t use public access computers for accessing personal information.
Public access computers are those in internet cafes, public wireless networks, and lab computer. You have no idea what malware may be installed. When you do use public computers, don’t forget to log out.