I have recently installed CyanogenMod on two of my smartphones – and I’m really happy so far. My Note 2 is as fast as never before.

The installation process is really simple: get the installer from Google Play and follow the instructions.

https://play.google.com/store/apps/details?id=org.cyanogenmod.oneclick

But pay attention: by installing that ROM, you automatically void your warranty.

PS: you need a PC and a USB cable to get the job done