• Find and Remove Duplicate Files

One of the trickiest things that can take up lots of drive space are duplicate files littering up your computer—this is especially true if you’ve been using the computer for a long time. Luckily there are great apps like Gemini 2 that can be used to find and remove duplicate files with a really slick and easy interface.

You can buy it on the App Store if you want — Apple had this one as their Editors’ Choice, but you’re probably better off getting it from their website, because they have a free trial available there.

• Empty Your Trash Cans

The Trash on a Mac is equivalent to the Recycle Bin on Windows. Rather than permanently deleting files from within the Finder, they are sent to your Trash so you can restore them later if you change your mind. To completely remove these files and free up the space they require, you’ll have to empty your Trash. But Macs can actually have multiple trash cans, so you may need to empty several.

To empty your user account’s main trash can, Ctrl-click or right-click the Trash icon at the bottom-right corner of the dock and select Empty Trash. This will delete all the files you sent to the trash from the Finder.

iPhoto, iMovie, and Mail all have their own trash cans. If you’ve deleted media files from within these applications, you’ll need to empty their trash cans, too. For example, if you use iPhoto to manage your pictures and delete them in iPhoto, you’ll have to clear the iPhoto trash to remove them from your hard drive. To do this, just Ctrl+click or right-click the Trash option in that specific application and select Empty Trash.

• Uninstall Applications You Don’t Use

The applications you have installed on your Mac are taking up space, of course. You should uninstall them if you don’t need them—just open a Finder window, select Applications in the sidebar, and drag-and-drop the application’s icon to the trash can on your dock. Some of these applications can be taking up a ton of space.

To find out which applications are using up the most space, open a Finder window and select Applications. Click the “Show items in a list” icon on the toolbar and then click the Size heading to sort your installed applications by size.

• Clear Out Temporary Files

Your Mac’s hard drive probably has temporary files you don’t need. These files often take up disk space for no good reason. Mac OS X tries to automatically remove temporary files, but a dedicated application will likely find more files to clean up. Cleaning temporary files won’t necessarily speed up your Mac, but it will free up some of that precious disk space.

Your web browser has a built-in option to clear out browsing data that you can use to quickly clear up a bit of space—but it’s not necessarily a great idea. These caches contain files from web pages so your browser can load the web pages faster in the future. Your web browser will automatically start rebuilding the cache as you browse, and it will just slow down web page load times as your browser’s cache grows again. Each browser limits its cache to a maximum amount of disk space, anyway.

There are a lot of other temporary files on your system, which you can see by opening up Finder, using Go -> Go to Folder on the menu, and using ~/Library/Caches to get to the cache folder. This will pull up a folder that has a ton of folders in it, which you can select and delete manually if you choose.

You can clean up temporary files easier, and much safer, by using CleanMyMac. Just open it up and run through a scan, and then go into the System Junk section to identify all of the cache files and other things that you can clean up. Once you’ve selected what you want or don’t want to clean, just click the Clean button.

One of the things that makes a utility like CleanMyMac so great is that it converts a lot of those confusing folder names into the names of the actual applications, so you can see which temporary files you’re actually deleting.

The thing about temporary files, of course, is that most of them are going to come back after you use your Mac for a while. So deleting temporary files is great, but only works for a while.