Today I open you the verities about the One X!
I can't be held responsible for anything wrong on your device. I have done that and it works for me! If you have some question, I can try to answer, but you are responsible if you brick your phone!
It took me 2 hours to succeed it, but this is not my first time, I already root: Desire HD, One S, Sensation, Sensation XE...
You need to take care! Moreover before starting you need to install the Android SDK!
Maybe you have to watch the video one time also before doing something!
You can follow my videos by this xda thread: The Utimate Stock to Custom Rom Guide (Thanks to The Last Hylian)
On this post I will not explain how to do, just post videos!
I don't want to keep the The-Last-Hylian work!
If you need help, please asked on his thread!
Can't foget to thanks, share & subscribe!