It seems trivial but many people don’t know how to change the Mac name. It is quite simple but not so straight forward. Do Follow these steps:
Step 1: In the Menu bar, go to > System Preferences…
Step 2: Click on Sharing.
system preferences sharing
Step 3: In the Computer Name box, type in the name you want to use for your computer.
change name of mac
Step 4: Close the window, and you’re done.
And its done, it is as simple as it gets ;).