Be warned! As of Christmas Day, the CyanogenMod nightlies for the GT-i9305 series have changed over to CyanogenMod 11.
YOU MUST FOLLOW THESE INSTRUCTIONS FOR THIS TO WORK.
Go hit this thread for info on the packages you’ll need. You will need, at minimum;
- ClockworkMod 6.0.4.5 (from that thread!)
- cm-11 Nightly Build (from get.cm will do)
- gapps-kk build (from that thread)
Then, in order to make it work, flash things in this order;
- Reboot your phone into recovery mode. MAKE A BACKUP.
- Flash the ClockworkMod ZIp. Reboot again.
- Flash the cm-11 build
- Flash the gapps-kk build
- Wipe the cache partition. Reboot.
- Pray
Good luck!