"Can I use your computer real quick?"
Depending on who asks you this question over the next week, reactions may range from nothing to frantic flailing toward your machine to see if you can make it do something that looks like it is unusable, getting you out of having to relinquish it to a family member with a checkered techno-past. Since you've already done the basics to protect your Mac, like set a screensaver password, what else can you do to family-proof your machine?
Luckily, a small bit of prep work can make this question easy to answer. All you have to do is whip up a guest account on your system. Guest accounts are perfect because logging in as a guest user limits the amount of damage that can be inflicted on your system to virtually nothing. Guest users can't change other user accounts or system settings and have no remote access. If you really want to ratchet things down, you can also use Parental Controls to limit the apps a guest account can use, or filter internet content.
While all of that is nice, one of the most important differences between a guest account and a regular account is files: Any files created or downloaded by a guest account are deleted on logout, so every time you log in as a guest user it always looks like nobody has ever logged in before.
If this sounds like the way to go for you, and you're running 10.5 or higher, here's how to create a guest account:
- Go to System Preferences and select Users and Groups (10.7) or Accounts (10.5 or 10.6).
- In that panel, click on the Guest User, and check "Allow guests to log in to this computer."
That's it! No really! All you have to do is determine whether you want to turn on Parental Controls or allow the guest account to connect to shared folders, and you're done. Now your Mac is ready for whatever your visitors can throw at it.