How To Install and Upgrade HTC One XL To CM 12 ROM

So you are using HTC One XL and bored of stock ROM which is not having features and also not customisable? I hope that's the only reason because of which you are searching CyanogenMod 12 ROM (Android 4.4.2 KK) for HTC One XL. You may have heard that CyanogenMod 12 is the best ROM, it is true! It is the best AOSP ROM you can have! I had bought Moto G just a week ago and I am running CyanogenMod 12 in it and it's is running smooth, with no bugs! My CM 12 ROM was a nighty release which means it was not stable, but for HTC One XL (evita), the release is fully stable and doesn't have any bug. The ROM will be as stable as your stock ROM. There is no Kit Kat update for HTC One XL, but you can tase the KK ROM by flashing this CM 12 ROM. CyanogenMod 12 ROM is just same as your stock ROM, but it can be customized! You can change the settings of how your notification bar appears, how your animations goes, guesture of your lock screen and other things. If you need a ROM which is customizable, has themes, then go for HTC One XL. Let me tell you that you cannot use themes in your stock ROM, but you can easily download and use themes in your CM 12 ROM. The ROM wil work in HTC One XL, because I personally tried this ROM in my friend's XL. It was a good experience when I put my hands on his device. I am also using CM 12 on my device and enjoying themes.
KitKat brings lots of functions in Android devices like new animations, more battery backup (ART), better multi-tasking, more stablility and better application support.

Pre-requists

• Make sure your HTC One's bootloader is unlocked and you are a rooted user.
• Make sure you have CWM or any other recovery installed in your HTC One XL.
• Don't flash this ROM on any other HTC or non-HTC device.
• Make a backup before flashing this ROM (included in the main guide).
• Don't try things not suggested here, because I won't provide support to the users who did it.

Downloads

• CM 12.1 ROM for HTC One XL: Click HERE.
• Google Applications (GApps): Click HERE.

How To Install/Flash CM 12 Android 5.1 Jelly Bean ROM in HTC One XL

• Download the ROM from your PC and move it to your SD Card.
• [Optional] Download Google Apps and move it to your SD Card as well.
• Reboot your HTC One XL to recovery.
• Select Backup and restore and select Backup option.
• Select Wipe user data/factory reset option.
• Go to Mounts and partitions and format /system from there.
• Select install zip from sdcard and select the SD Card. Then select the .ZIP ROM which you just downloaded and pushed to your SD Card.
• Flash the Google Apps with the same method as well! 
• Again select Wipe user data/factory reset option.
• Select Reboot system option and wait till the device reboots!

This bot will take more time than usual, but after this boot, other boots will be faster like your stock ROM.

Update: added link for cm 12 based on Jelly Bean!! :D