Visit the Apple Support page and click the Download button to receive the InstallMacOSX.dmg file. Open the DMG: Double-click the downloaded file to mount it.
This installer is with any Mac that originally shipped with Mac OS X Mountain Lion (10.8) or later. If your Mac is running a very old version like Tiger (10.4) or Leopard (10.5), you must first upgrade to Snow Leopard (10.6) before you can install Lion. Mac OS X Lion 10.7.5 Free Download
You can download the official DMG installer directly from the Apple Support Download Page . Visit the Apple Support page and click the
Open the "Install Mac OS X Lion" app from your Applications folder and follow the on-screen instructions. Important Compatibility Note Mac OS X Lion 10.7.5 Free Download