NOTE: Before you can even do what is on this page, you will need to make sure you have followed all other steps in my guide on how to install a custom rom.
Recommended ROM to install is the Google Play Edition by Danvdh, Kryten2k35, Googy_Anas & Ktoonsez
Link
(download link for latest build is half way down the page)
There are many roms flying around, i tried a few of them and i never liked them, i kept going back to the Google Play Edition by Danvdh. Its clean, fast and no bloat what so ever.
Up till recently 4.x was available but now since the release of Lollipop v5.x its been recently updated.
Lollipop is better than ever and will only keep getting better as they add new features to it, i highly recommend you install v5 over v4.x Kit Kat.
1. Download the above file, then plug your phone via usb to your computer and transfer the zip file to the SDCARD root level directory. If you have a microsd card in your phone i recommend you copy it to the root of that rather than the root of your phone.
2. Reboot your phone in recovery mode.
3. In recovery mode do the following, WIPE DATA / FACTORY RESET. Go back and select WIPE DALVIK CACHE. Once finished, choose INSTALL FROM ZIP, select the zip file you copied to the root of the sdcard, select YES to install.
4. Let the magic happen, go through the installation process of your new ROM. Your done.
NOTE: Please make sure you have performed a nandroid backup first of your original OS so that if something goes wrong you can revert back to default.