Well, what you should do is erase all data on the phone, then set it up as your phone. So, do this:
1. Turn off iMessage.
2. Turn off FaceTime.
3. Delete the iCloud account...Settings>iCloud...scroll down, delete account.
4. Settings>General>Reset>Erase All Content & Settings.
When finished, name it what you want & sync your content to the phone.