Keep your Mac running smoothly
Here are a few things to take care of, maintenance-wise
The good news is that recent versions of OS X have all but eliminated the need to perform regular maintenance on your Mac. You no longer need to periodically defragment your hard drive, run Unix cron jobs, or clean caches. There are, however, a few things you can do to prevent problems and keep your Mac running smoothly.
The first and most important is to implement a regular, automated backup schedule – regularly! Automatically! At the very least you should switch on Time Machine and use it to back up data to an external hard drive or NAS. Ideally, you should also have an off-site back-up routine using a service like CrashPlan or Backblaze. If you want to be really safe, you could clone your entire drive regularly using SuperDuper! or CarbonCopyCloner.
Back-up aside, if you’re using a version of OS X earlier than Mavericks (which sandboxes Flash), consider disabling the Flash plug-in in Safari (if you need to view Flash content, read about workarounds at daringfireball.net/2010/11/flash_ free_and_cheating_with_google_chrome).
Periodically check your Downloads folder and remove installers and disk images you no longer need – it’s an easy way to reclaim hard drive space. Upgrade the RAM if possible.
Tools such as Cocktail or Maintenance will run scripts to repair permissions, reset Spotlight’s index and more. They’re less necessary in recent versions of OS X, but especially if you’re running Snow Leopard or older, they may help keep things running smoothly.
Periodically restart your Mac; once every week or two is fine. Quit and re-open Safari once a week or so. Close any tabs you no longer need, and Empty the Trash regularly. Keep an eye on the health of your boot drive using a tool such as TechTool Pro, DiskWarrior, or Drive Genius.
You should also keep software up to date. Apps downloaded from the Mac App Store will update themselves, but for other apps switch on the option which allows them to periodically check for updates. Don’t ignore updates to OS X from Apple, but give them a few days before installing and use Google to check for issues before you hit Install.