There is no way to copy the permission settings from one person to another, but you can move them.  

For example, if your current CEO is leaving and your new one is starting tomorrow, you can move all of the settings from your old CEO to your new one.

To do this go to Tools > System Utilities > Admin Utilities > Mass Change Security Permissions
Enter in the From and To security id's and click OK.  

This process performs a global substitution throughout the Permission table.