Setting up a USB 4" x 6" Zebra label printer on your Mac can be done in just a few steps. If you need help installing the printer on Windows, please read this article.
The first step will be to add your printer. Here's a .GIF for adding a GC420d. The individual steps for this process are listed just below the .GIF!
Head to System Preferences under the Apple Menu () in the top left corner of your computer screen.
Then click the Printers & Scanners icon.
Next, click the + button under the Printers window. From the dropdown, click Add Printer or Scanner...
On the page that appears, select the printer you wish to add.
From the Use: dropdown, click Select Software... and in the Printer Software popup, select Zebra EPL Label Printer. Then click Ok.
Once you click Add, the printer will be saved!
The next step in the setup process will be going in to CUPS to make sure your printer is set up to print out labels as 4"x6". For a detailed setup process on this, head to this article!
After the printer is properly-configured, you can set it up to print through ShipStation Connect.
Congratulations, you finished installing your Zebra printer!