- 1 - Of course, if you’re running Mac OS X 10.5 or later and have an 2nd hard drive, then Time Machine will do the job most transparently. - 2 - Software like Carbon Copy Cloner (free) or SuperDuper! (paid) can do the job for you. They have builtin scheduling preferences. - 3 - If you want develop something yourself, you can look into learning about rsync, which is what CCC uses behind the scenes to do its work. And yah, you could develop a workflow in Automator or, if you want to keep it low-level in UNIX-land, consider using cron as your job scheduler instead.