To edit the default settings for a printer on a Mac, you must edit your CUPS (Apple's printing software) settings. CUPS is an open-source printing system that allows you to set up a printer on a Mac.
Before we get started, make sure that you have already setup your label printer on your computer.
Once you've confirmed your printer is added correctly in System Preferences, open your internet browser and type (or paste) the following link into your browser's address bar:
If you receive a "web interface error" that means your Mac is not yet configured to allow access to CUPS. You'll need to enable this option in the Terminal utility app. If you are able to access CUPS, skip the step involving the Terminal app.
Open Terminal from the Spotlight Search in the upper righthand corner on the Menu Bar of your computer screen.
In Terminal, copy and paste the following command after the $ sign:
Then press Return on your keyboard.
Quit Terminal and go back to your internet browser. Type the following link into your browser's address bar once again:
On the page that appears, click on the printer you wish to edit. For this example, we are configuring the Zebra LP 2844:
On the next page, click the Administration drop down menu and choose Set Default Options.
If a popup Authentication Required appears, you'll need to enter your computer's admin user credentials.
(If the password has been forgotten, you MUST contact Apple support. They can be reached at: 1-800-MY-APPLE (800-692-7753)).
You should not be in General Options.
Change Media Size to "4.00x6.00" and then click Printer Settings at the top. Do not click Set Default Options just yet.
On Printer Settings, adjust the Darkness and Print Rate:
Print Rate: 2 inches/sec.
Then click Set Default Options.
Congratulations, you're done! You should now see a message similar to the image below.