Do not use a blank password on your personal computer
You should make sure have string passwords for all acounts on your computer, it consist of at least eight charcteres long, does not contain your user name, real name, or company name, and contain uppercase and lowercase, numbers, and symbols found on the keyboard (#,$,etc.).
Change your password frecuently (every 30 days as minimum)
Download and install important security and other recommended update on your operating system
Note tahr is not only enough update your operating system, you must be too update applications installed on your computer, e.g.Web browser, instant messaging software, media players, etc.
Install, manage, and update antispyware software
Install, manage, and update antivirus software
Use a personal firewall, it'll maintain protected your computer against attacks
Never double-click on an email attachment that contains an executable program
Use antivirus software to scan any files, programs, software, email, attachments, USBs, CDs or diskettes before you use them on your computer
Protect your computer
Install an Anti-phishing Toolbar or Web browser whith this feature if you ue banking services.
Don't disclosure personal informacition (credit card numbers, social security numbers, etc.) on Websites email links; it would be a phishing scam attack.
Install and update software antivirus before to use software pear-to-pear (e.g. Emule, LimwWire, etc.)
Don't dosclosure personal information when uses instant messaging application (Windows Live Messenger, ICQ, Skype, chat rooms, etc.)
Configure properly your home wireless network; it may being used by unauthorized users.
Be careful whit emails, it waiting for innocent people to fall into their traps an steal money; it asking you a payment to 'release' some much larger amount which is held by a third party.
Be careful whit Virus hoaxes, usually are false reports about non-existent viruses, often claiming to do impossible things. Unfortunately some users occasionally beleive a hoax to be a true virus warning and may take drastic action (such as delete some file on the computer).
Spend a little time to perform periodical backups of youy information.
Public sites
Do not log in to online banks or financial services from hotspots.
Avoid visiting high-risk pages, like hacking and pornographic pages.
Try to avoid to download software in hotspots and never copy them to other computers.
Do nor send emails containing personal information, these can be intercepted by third parties or can be stored locally.
Disable the automatic storage and auto-complete feature in Internet Explorer and Firefox.
Disable the automatic password storage in MSN, Yahoo, Google Talk and any other messenger service
Try to avoid to log in with your username and password as long as the hotspot can contain keyloggers.
Verifity that the antivirus and firewall are all enabled in the computer you are working with.
If you insert some storage medium (like external HD, USB memory, etc.) in public computer, remember that you have to scan it with an antivirus prior to connect it to you peronal computer
Enterprise network
Define a network use policy for your network.
Use full disk encription policy on all mobile devices.
Audit your firewall policy.
Use password encription capabilities on your routers.
Define a level of trust for every security zones on your network (DMZ, Perimeter, WiFi, Internal Network, etc.).
Implement network security monitoring within your network.
Implement a VPN for your remote access from trusted clients to your network.
Use encryption, even if it's only WEP, Prefer WPA2, upgrade the hardware to dupport this (if needed).
Trun off wireless and Bluetooth on your laptop when you don't need it.
Don't allow dual connectivity just one network connection at time for your wireless clients.
Don't allow a separate connection to a network of a lower security classification like P2P.