Here is a quick step by step from one newbie to the rest. Its a copy paste of multiple posts.
1. Root phone using any of the root methods. (I used the pay
Easy Root App. $1 is totally worth it.)
2. Download the updated version file. (Pick the one you want. I used the
Op's 2.2)
3. Rename file to update.zip
4. Download the file to the sd card
5. Restart the phone by pressing power and x at same time.
6. After you get the yellow triangle, hit the volume up and camera button at the same time
7. Use the d-pad to navigate to the “apply: update.zip” option, and choose the file you just dragged onto your microSD card.
8. When done, choose Reboot system.
9 Verify everything is working.
10. Reroot, if you choose. (I did.)
(Optional) Do a battery pull for good measure.