Start by 1. Install drivers: http://downloads.unrevoked.com/HTCDriver3.0.0.007.exe 2. Put phone in full boot, usb debugging on , charge only. 3. Uninstall HTC Sync or any other sync application if installed.
After that download Revolutionary from revolutionary.io. Connect your device. It will ask for an beta key. You can retrieve that as follow: http://revolutionary.io <-- click a download link for the beta form, fill that out. If the form does not show, enable javascript, or disable noscript extensions and such.
COPY PASTE YOUR SERIAL NUMBER AND THE BETA KEY TO THE REVOLUTIONARY WINDOW.( Copy paste like this: To copy and paste into revolutionary follow step 6 here: http://bit.ly/qsBzzD).
After Revolutionary has finished. Select bootloader and then go into recovery. If you see Revolutionary CWM then proceed to the next step, which is rooting, like this :  Download http://goo-inside.me/superuser/su-3.0-beta4-efgh-signed.zip and do not extract it. Place it on your sdcard, and install from ClockWorkMod recovery.
Otherwise if you see exclamation marks: Flash cwm manually like this: To manually flash ClockworkMod - http://bit.ly/cwmguide.

You can get into hboot by: Pull the battery, put it back, power up holding volume down button.
Get into recovery by getting into hboot and afterwards selecting Bootloader > Recovery.