Sell it locally if you can, on Craigslist or Kijiji preferably. There are a lot of scammers out there so I always try to sell something in person, if possible. Never accept checks or any sort of bank draft. Cash only! If you must sell it online you can use a service like PayPal but that's still not fool proof from being ripped off. Be wary of anyone offering to over pay you, that's a common tactic with scammers.
Also make note of the email addresses, if someone contacts you with a hotmail.FR or some unusual address that appears to be from another country or something that just doesn't seem right, delete the message and move on. You might risk losing a sale, but for the most part people will email you from one of the more well known companies like Yahoo, Gmail or Hotmail.