How to Unlock iPhone 3G with YellowSn0w | Step-by-Step Guide

In this iPhone tutorial, we will guide you on how to unlock iPhone 3G to make use of all carriers’ SIM card on your iPhone.
This guide is for iPhone 3G users ONLY. iPhone 2G users: Learn How to Unlock iPhone 2G.
Update for iPhone OS 3.0:
How to Jailbreak/Unlock iPhone 2G OS 3.0 (MAC)
Prerequisites
You must Jailbreak your [...]