Here are my key steps
in keeping a computer protected
Keeping your software & OS up to date.
Keeping either a bi-directional firewall installed/up to date and running at all times or a Unified
Threat Management system like our Untangle Network Gateway.
Keeping an up to date antivirus/antispyware installed & active always.
Running scans on a regular basis with AV software.
Staying off the P2P sites or sites that offer cracked software.
Being very careful on social networking sites. I won't click links posted unless I can verify it is
safe.
Watching what I download. If I want to try out an app - I try to research about it & read
reviews.
If it is free ... why?
I don't open emails I am not expecting and those that I am I handle with care. Attachments are never
opened right from the email I always save them first. If I am not sure - I will ask sender what the file is
supposed to do & if they meant to send it.
Spam is outright deleted. I suggest using antispam software like Mailwasher Pro. Ecards/postcards
deleted - (unless I know/trust the sender and even then I ask first)
Watching the kind of of search results that come up & being choosy which results I click. I
primarily use Google for searches. Google has improved things somewhat by labeling possibly harmful sites
but I also see in search results often a lot of really odd looking "code" or rather parts of scripts. I
stay away from this because a lot of the time it is a hacked site and what I am seeing is part of the
malicious javascript designed to exploit the PC which leads to infection.
Not clicking links in IM/IRC/Chat programs unless I can determine for sure it is safe.
Not accepting files in IM/Chat unless I can trust the sender & I have asked what the file is/know
what it does.
Using common sense.
Back up important stuff regularly & preferably have the backups kept on offline storage. I use an
external hard drive which is only connected when I do my backup.
If a PC on your network is found to be infected - get it off the network so it does not spread.