Trying to tether to my computer and then to my Xbox 360 to download some updates.

[CXTKRS1]

I tried searching for a thread but no luck or at least I couldn't find exactly what I needed. I'm looking to tether my Thunderbolt to my laptop and then run an network cable to the back of my Xbox 360. I run on 3G only and I am not looking to play online but just download some updates I need.

Thanks.