Restore it in iTunes. Then when iTunes says "Do not unplug your iPhone. It is restarting." Unplug your iPhone. When your iPhone is done restarting, press the power button and turn it off. This way when the buyer gets the iPhone, it'll be just like a factory fresh iPhone. Don't forget to remove your SIM card if your iPhone has one.
I would remove the sim card before restoring in iTunes, that way you don't have to unplug it during the install process.Restore it in iTunes. Then when iTunes says "Do not unplug your iPhone. It is restarting." Unplug your iPhone. When your iPhone is done restarting, press the power button and turn it off. This way when the buyer gets the iPhone, it'll be just like a factory fresh iPhone. Don't forget to remove your SIM card if your iPhone has one.
I would remove the sim card before restoring in iTunes, that way you don't have to unplug it during the install process.
It's still a good idea to unplug it while the iPhone is restarting. This prevents iTunes from putting anything back on the iPhone and it makes the iPhone restore to a factory fresh state.
the question is : did it remove everything like when restoring by itunes ?