Use a Mac long enough and you’ll eventually stumble upon forums like the “Post Your Desktop” threads at sites like MacRumors. Mac users love to customize the look and feel of OS X, and one of the easiest ways to do it is by using custom icons for your apps and utilities.
Apps like CandyBar have long offered a quick solution to managing your Mac’s application icons, but it’s just as simple to change most icons yourself. Here’s an overview on how to use custom icons in OS X.
OS X includes a number of “special” applications (e.g., Calendar, Finder, Trash) that need some specific attention when it comes to changing their icons, and we’ll discuss those more below. For most apps, though, the process is fairly straightforward.
First, identify the app you want to modify and find a suitable replacement icon. In our example, we’ll change the icon for iTunes in our OS X Mavericks installation to the Yosemite iTunes icon teased by Apple during WWDC. You can use practically any JPEG or PNG image file as an icon, but you’ll see the best results with uniformly sized PNGs with transparency. Great places to find replacement icons that are properly formatted include deviantART and the MacRumors forums.
Download the image you’d like to use as your new icon and open it in Preview. With the image open and Preview the active application, press Command-C to copy the entire image.
Next, find the original location of your app (not it’s Dock or Desktop shortcut). For almost all applications, you’ll find the correct file in your Applications folder, located at Macintosh HD/Applications. In our iTunes example, the iTunes.app file is found in the top level Applications folder. If you want to change the icon of a system utility like Activity Monitor or Terminal, you’ll find these apps in the Utilities subfolder of the Applications folder.
Quit the app if it’s running and then highlight it in Finder. Press Command-I to open the Get Info window. Alternatively, you can right-click on the application and select “Get Info.”
Here, click on the small application icon preview at the top of the window, to the left of the application name (not the larger icon preview at the bottom of the window). You’ll see the icon preview outlined in blue once you’ve correctly selected it.
Now press Command-V to paste the image you copied earlier. You’ll see both icon previews change to display the new icon, and you can close the Get Info window if you’re satisfied with the new look.
If you don’t like the way that the new icon looks, you can press Command-Z to undo the change, or highlight the small preview icon at the top of the window and press Delete to revert to the default icon.
Once you’ve made your changes, the new icon will be displayed in Finder or via Desktop shortcuts. To get your new icon to show up on the Dock, either quit and relaunch the app or head to Terminal and enter the following, case-sensitive command:
Repeat this process for each app icon you wish to modify and you’ll soon have a slick custom Dock. Now, what about those special apps we mentioned earlier? We’ll show you how to change the icons for Finder, Calendar, and Trash on the next page.