Best approach to update and apply CUs for SharePoint farm . should i manually install CU or i should use windows update

I got confused on how i should update my SharePoint 2013 farm. for example now my windows update tool mentioned that i have 4 updates for SharePoint 2013 regarding December 2014 CU. now some articles says that it is better to manually install these updates while other are saying that using windows update tools is the recommended approach since it will only show the necessary updates based on my current farm settings. can anyone adivce on this please?