I’m pretty sure ive had both but im not experienced enough to know taste difference and i cant tell by its appearance.
Here’s one of the best resources on the Internet for identifying counterfeit Cigars. Don’t kid yourself, even so-called experts can be fooled, and even cigars purchased at Casa del Habano have been found to be counterfeit.
http://www.cigaraficionado.com/Cigar/CA_Counterfeits/Counterfeit_Gallery/0,3390,,00.html

smok it and inhale if u cough its not
References :
Send it to me … I’ll "analyze" it for you
All submissions become the property of me.
References :
I assume you are not in the US, and you are inquiring about Cuban Cohibas. The best indicator is where you purchased the cigar. A reputable cigar store would be your best place to find them.
References :