Can any iPhone Expert Guide me

[haissk]

My Friend is on iPhone 3g with 3.0 OS jailbreaked but locked to AT&T and 5.11.07 baseband
Can anyone guide him the detail steps on how can he upgrade for 3.1.2 and blackra1n
When he restores the 3.1.2 firmware through iTunes he is now having Data Cable and iTunes logo in his screen

Note: He does not have original AT&T SIM

[SundayDuffer]

plug the phone to itunes just to make sure that it connects..now run blackra1n..ignore itunes while doing this process. Once done, on the phone click on blackra1n and install Cydia and Blacksn0w..let it runs. After that youre good to go..customize the phone as usual. he doesnt need the sim to be in the phone while blackraining.