It's really simple.
First, get the hboot drivers on your pc through the unrevoked guides.
Also through that guide decide what erase size you are and download amonra recovery if you're 40000.
Also read the fastboot guide and make sure you can run that by opening up the cmd command.
Download the root file from the revolutionary website and put it on your SD card.
Run revolutionary (extract zip and run program) and follow prompts. If your 20k erase size then have the revolutionary software install clockwork recovery, if 40k, say no to it.
You should now be s-off but not rooted.
If you have no recovery yet, boot into fastboot, open cmd on pc and type fastboot flash recovery c:/recoveryxyz where the c:/ ..... Is the location and name of your anon-ra file.
Once you have recovery, boot into that from hboot, and chose option to load a zip. Pick your root zip you downloaded onto sdcard, and once dine you reboot and youre rooted and soff!