This is advice that Apple does not give you when you buy your Mac. After all they want people to believe that there are no vulnerbilites or any system problems. I admitt I have had few problems but there are a few things you can do to set up your Mac to be even more secure and easier to troubleshoot when you do have a problem.
Create a minimum of three accounts:
User Account: You will always want to use your User account for all your regular work and especialy the internet. The reason for this is if any one would ever happen to beat your security they will only have access to a unprivileged account. When you do install software or do anything to change the system, the Mac operating system will ask your permission. When in your User Account you will need to respond with the Administrators name and password. The Mac operating system is thus insuring security, nothing is installed or changed without your permission.Troubleshoot: You will leave this account unused. Its purpose is to act as a baseline in case you have any system trouble. One of your very first troubleshooting steps should be to know if the problem is with the User account or the System. If the problem exists in Troubleshoot (as well as your account) then the problem is with the System. If switching to the Troubleshoot makes the problem go away then it is just a problem with your account.