Make sure your built-in Mac firewall is enabled in System Preferences > Security > Firewall
Uncheck "Open "safe" files after downloading" in Safari > Preferences > General
Disable Java in your browser (Safari, Chrome, Firefox). This will protect you from malware that exploits Java in your browser, including the recent Flashback trojan. Leave Java disabled until you visit a trusted site that requires it, then re-enable only for the duration of your visit to that site. (This is not to be confused with JavaScript, which you should leave enabled.)
Change your DNS servers to OpenDNS servers by reading this.
Be careful to only install software from trusted, reputable sites. Never install pirated software. If you're not sure about an app, ask in this forum before installing.
Never let someone else have access to install anything on your Mac.
Don't open files that you receive from unknown or untrusted sources.
For added security, make sure all network, email, financial and other important passwords are long and complex, including upper and lower case letters, numbers and special characters.
Always keep your Mac and application software updated. Use Software Update for your Mac software. For other software, it's safer to get updates from the developer's site or from the menu item "Check for updates", rather than installing from any notification window that pops up while you're surfing the web.
That's all you need to do to keep your Mac completely free of any Mac OS X malware that has ever been released into the wild. While you may elect to use it, 3rd party antivirus software is not required to keep your Mac malware-free.
It's always surprised me it's turned off by default. Although I suspect it only monitors incoming connections not outgoing, meaning if you are behind a router using NAT without specific port forwarding then there's probably no real benefit anyway.
One problem I seem to have is XMBC always asking for permission to accept incoming connections. No matter how many times I say yes (or no, for that matter) it asks me each time it starts. Adding the exception myself doesn't seem to help either.
One problem I seem to have is XMBC always asking for permission to accept incoming connections. No matter how many times I say yes (or no, for that matter) it asks me each time it starts. Adding the exception myself doesn't seem to help either.