How to change the login screen on iMac?

[Unubis]

Can anyone help me on as to how I can change/Customise the login screen on my iMac? I have done it with the last system (Changing the PNG picture in the Cache folder) but now its not working.

 

[thejasonhowell]

Can anyone help me on as to how I can change/Customise the login screen on my iMac? I have done it with the last system (Changing the PNG picture in the Cache folder) but now its not working.

Use an app called Onyx

 

[Ericclark4]

helpful, thank you