How do I upgrade hboot from 0.43.0000 to JB?

Jan 15, 2013
As far as I understand, I need to upgrade my HBOOT to make a JB MIUI rom work on my Htc One X.

I'm totally new to this, and I really don't know what HBOOT is, I have just used it.

Is there a guide anywhere and/or can anyone point me in the right direction? This seems like something that could brick my phone if done wrong :(

Edit: Current version is 0.43.0000