- Find the downloaded file, which usually ends up in your Desktop or Downloads folder.
- Double-click the .DMG file to mount it. A new Finder window showing its contents should appear.
- If the window also contains a shortcut icon to “Applications”, drag and drop the app onto the shortcut.
- If not, double-click the mounted volume on your desktop and drag the app icon from there to the “Applications” icon in the Finder sidebar.
– See more at: http://www.ofzenandcomputing.com/how-to-install-dmg-files-mac/#sthash.JrjNvx1g.dpuf