The default black type on white screen window that comes as default in OS X Terminal is functional, but it’s really not that fun to use. Adding in color and some contrast is a good way to keep your aesthetic sense engaged, as well as make Terminal a bit more useful. In fact, there are many other themes built right in that do just that, and several you can download and install from the web.
Here’s how to change to one of the built-in Terminal themes, and a bit more on how to install third-party ones to boot.
Launch Terminal and hit Command-Comma, or go up to the Terminal menu and select Preferences… Next, click on the Settings tab at the top of the preferences window, and look down the left-hand column. Notice all those different icons there, with names like Homebrew, Man Page, Novel, and Grass? Those are themes. All you need to do to create a new Terminal window with that theme is to double click on the icon in the left pane.
Each theme contains a ton of different tweaks to the text format, the window color and the like, all of which can be found to the right side of the theme icons. If you want to mess about with the Red Sands theme, for example, you simply need to click on the Red Sands icon in the left pane, and then check and uncheck the specific preferences over in the right pane. Click on the gear icon at the bottom there to Duplicate the settings you’ve tweaked, and save it as a differently named theme.
To grab a third-party theme, simply head to the web site that has the theme file, download it, and then double click it once it gets downloaded to your Mac. The file will be be affixed with a .terminal file extension, and Terminal app will open when you double click it, asking you if you want to open it. When you say yes, it will open a new window in Terminal with the specific theme settings. Here are a couple of themes you can try out: IR_Black, and Peppermint.
Via: OS X Daily