Following a recommended maintenance schedule for your iMac will help you avoid problems and keep your computer running smoothly. Use this iMac maintenance guide as a handy reminder.

Task Schedule
Check for updates within the App Store Automatic setting (App Store pane in System Preferences)
Back up with Time Machine Automatic
Defragment (using Prosoft Engineering Drive Genius 4) Once a month
Delete unnecessary user accounts As necessary (Users & Groups pane in System Preferences)
Scan for viruses (using Intego Mac Internet Security X8 or ClamXav) Automatic
Check all volumes for errors (using Disk Utility) Once a week
Check for the latest drivers for your external hardware Once a month (or after adding new hardware)
Delete temporary Internet cache files and old system logs (using Rocky Sand Studio's Disk Diag) Once a week