This unofficial build of CyanogenMod 13 for the Kindle Fire HD 2012 is a great ROM that still has some bugs since it is an unofficial port made by ‘transi1’, you can find the XDA post for this ROM here. Make sure you have at least 70% battery before flashing this ROM.
Reboot into Recovery, if you don’t have one learn how here.
Make a backup just in case something goes wrong and you need to restore to a previous state.
Click ‘Wipe’ and swipe to factory reset, this MUST happen (This does not wipe your Internal Storage don’t worry)
Then press ‘Install’ and navigate to the folder where you downloaded the CM13 and tap it.
Swipe to confirm flash, this will take a while DO NOT cancel.
After it is done DON’T press reboot system or you will have no Google Apps and you will experience errors.
Click ‘Home’ and then once again ‘Install’
Select the ‘gapps 6.0′ file and once again wait. Once done press reboot system
First boot up may take a while however if it takes more than 10 minutes hold the power button till your device goes off and try turning it on again.
If it still won’t boot go back to recovery and restore your backup
If everything works then enjoy your new ROM!
Watch the video here.