How to prevent your laptop from automatically updating to Windows 8.1?

I have Windows 8 on my Lenovo G500. I'm completely content with Windows 8. Last time I updated to Windows 8.1 it would not allow my laptop to access internet or anything. How do I disable the automatic update? I can't get any work done with it interrupting me.

Go to control panel->system and security->windows update-> select never auto update