Create a secret admin account
How to hide an administrator account from general view for added security
Follow these steps and when someone logs into your Mac, they will see no username options for the hidden account
Creating an admin account that is hidden from other users is very useful for a number of reasons. The obvious one is that people cannot attempt to make use of it and, although it is not necessarily a sophisticated security measure, it will be more than enough to stop most people knowing that it is even there. The other reason is more generic, but having a second admin account makes sense just in case you lose access to the main account, at which point it can be used to recover from major problems that you may otherwise be locked out of. The process is fairly straightforward but you will need to be precise to ensure that you do not lock yourself out of your Mac. As is always the case with Terminal, type carefully and make sure you put the spaces in the right place.