]MacBook Pro 13-in Late 2011 model not syncing to AirPlay

I have a MacBook Pro 13-in Late 2011 model. I bought an AppleTV this past December 2013. I can get my iTunes to sync to AirPlay but not my computer. According to the site, I have the appropriate model of computer. Any ideas how to sync up my laptop to Airplay to where I can mirror? I tend to find myself semi-tech savvy, by no means am I a genius, but I can normally follow instructions. I just haven't had luck!

Thanks!