To perform a few simple maintenance scripts on your Mac, I would recommend just using Terminal. Although your Mac automatically runs these maintenance scripts at 3-5 AM (if your Mac is on), it is still a pretty good idea to run these scripts manually just to clear any problems up you may be having.
Here are instructions on how to run maintenance scripts on your Mac:
Go to Finder > Applications > Utilities > Terminal.
When Terminal loads up, type in sudo periodic daily weekly monthly
Once you have typed all of that correctly, hit the Return key.
After hitting the Return key, you will be asked for your password.
There will be a time in every Mac user’s life where they will have duplicate images in their iPhoto library. I am aware that when importing images into iPhoto, there is an option to skip duplicates, but this only works while importing, not after the pictures have been imported. When I had to restore my iPhoto library from my external drive, iPhoto grabbed my originals folder and the data folder. For some reason, this caused more duplicates than I could ever have imagined. I found a miraculous AppleScript-based application called iPhoto Diet which will safely remove the duplicates and place them in iPhoto’s trash or into a separate duplicates folder within iPhoto. Trust me, this is an application you want to keep around for that one time you’ll need it.
Whenever I have wanted to get some plug-ins for Photoshop or some great apps for my Mac they sometimes come in a “.sit” or a “.sitx” file. The reason being that “sit(x)” files are compressed making them more portable and accessible to others. The solution to opening these files is to download the freeware application Stuffit Expander. Stuffit Expander will open anything from a .sitx file to a .bin file. I highly recommend keeping this Mac app, as it will come in handy whenever you need to download something from the internet. Note: another application that opens up “sit(x)” files is The Unarchiver (freeware) — it works with more file-types and is open-source, which is one main reason I like The Unarchiver much better than Stuffit Expander.