macOS: Check for and Install updates to macOS

1.  Click on the Apple menu in the upper left, and select 'System Preferences'

2.  In the System Preferences window, click on 'Software Update'

3.  In the Software Update window, follow instructions as they appear.  If updates are available for your system, a list will appear, along with an 'Install' button, which will proceed with installing those updates immediately.

4.  Note that "Updates" and "Upgrades" are different.  Updates are smaller, specific fixes of existing systems and features, while upgrades are larger changes to more numerous systems that both take significantly longer to install, and are much more likely to require restarting the computer, and potentially more likely to result in incompatibilities. 

Usually, upgrades include an installation wizard which will check for any such incompatibilities as are known, and allow you do address them or opt out.

5.  When your system is fully up-to-date, you'll see a window like this.  Note the checkbox for 'Automatically keep my Mac up to date'.  

6.  LTS does recommend checking this off, and selecting all options, especially for assigned machines that are frequently left on and connected to the Lehigh LAN.