confusion with unlock
please help! this is so confusing to me. will try to simplify.
my sister gave me her 3g after she upgraded. we are waiting for an unlock code from at&t. i use t-mobile.
1. when we receive code, do we restore backup on her intunes since she has her settings on there? or on my itunes?
2. do i have to have my new sim card from t-mobile first or later? i believe i have a micro sim card, understand the 3g uses standard.
3. does this need to be done at my house so it will pick up MY wi-fi? again, do i need to go to t-mobile first and get sim card?
please help, i want to do this correctly as not to mess up anything in the iphone or with her new upgrade.
thank you in advance.
MacBook Pro (13-inch Late 2011), iOS 5.1.1