How to update my jailbroken iOS 6.1 iPhone to iOS 6.1.2? I had jailbroken my iPhone last month when I was using iOS 6.1, and currently iOS 6.1.2 is available, which solves some battery issues (I am really suffering from these), so I want to update to iOS 6.1.2.

Would you kindly give simple steps to do that so I don't damage my device? I am not much of an expert on this, so your help is very welcome.
It is recommended to update your Jailbroken iOS device by doing full restore form iTunes. In order to preserve your apps, contacts etc. perform a backup in iTunes by right clicking on your device and selecting back up option.