If you are running Windows 8 on your desktop computer, you can skip this post.
But if you’re like me, and you are still using Windows 7, and you purchased a Windows Phone 8, then you need to install the Windows Phone App for Desktop, a free download from Microsoft. Please note that as of this writing, this app is still considered Beta.
Go to http://www.windowsphonecom/en-US/how-to/wp8/windows-app-for-desktop
Click on the Download now link
Click Run –> I accept… –> Next –> Next –> Install. If everything goes smoothly, you can click Finish
You can locate your Windows Phone app from the start menu: