First thing that everyone should know is that Unlocking is different from Jailbreaking. Unlocking is the process of making the phone useable for all networks whereas Jailbreaking is opening the gates to that process. Unlocking the phone is very easy. You just have to have a jailbroken iPhone with Cydia installed.
1. Again, using wifi or 3g connection, just open Cydia then tap the 'Sources' tab.
2. Under the sources, you should find the repository repo666.ultrasnow.com.
3. Tap that source and you will be presented with the option to install Ultrasnow.
4. Check first if your baseband is supported before installing because some devices like iPhone 2g do not rely on Ultrasnow to unlock and some other basebands like 5.14 cannot be unlocked using this.
5. If the device is compatible, just install then confirm then reboot your iPhone.
6. After it boots, it should search for a network and you will be able to use the phone functions.






