Trying to update from Yosemite to Sierra. Downloaded InstallMacOSX as per instructions on this page and ran but nothing happens. What else do I need to do? The installer runs through and is complete but no change to os?? help

Trying to update from Yosemite to Sierra. Downloaded InstallMacOSX as per instructions on this page (below) and ran but nothing happens. What else do I need to do? The installer runs through and is complete but no change to os?? help

Safari downloads the following older installers as a disk image named InstallOS.dmg or InstallMacOSX.dmg. Open the disk image, then open the .pkg installer inside the disk image. It installs an app named Install [Version Name]. Open that app from your Applications folder to begin installing the operating system.

• macOS Sierra 10.12 can upgrade El Capitan, Yosemite, Mavericks, Mountain Lion, or Lion
• OS X El Capitan 10.11 can upgrade Yosemite, Mavericks, Mountain Lion, Lion, or Snow Leopard
• OS X Yosemite 10.10 can upgrade Mavericks, Mountain Lion, Lion, or Snow Leopard