Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
What exactly do you mean by "clone"?
If you only want to create a copy of the application file, then: option/alt + drag
 
What exactly do you mean by "clone"?
If you only want to create a copy of the application file, then: option/alt + drag

I want to open the application twice at the same time, but each one having their own files.

Thanks
 
I want to open the application twice at the same time, but each one having their own files.
I gave that a brief try. Prefs (plist files), and process names will be identical unless you change them in the App's package(s). Changing package contents is likely to trigger a checksum error.
It's probably doable, but not casually. AFAIK, no one hacks Apple apps that hard anymore.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.