1) First, go to the official website to download the latest version of Apple's itunes installed on your computer. Or directly Baidu search for "itunes download." itunes is connected to your device and the computer, the computer's hard drive, only the computer installed itunes, iphone5S will respond when connected to the computer.
2) If you just put iphone5S connected to the computer, downloaded after installing itunes, as long as the data cable to connect iphone5S with the computer on it. But the next step is to operate through itunes right iphone5S need to do the following two points.
① Open itunes, registered Apple ID.
② The current computer authorization, only authorized only after synchronization applications, music and so on.
Recover iPhone Data from iPhone or iTunes Backup
How to Recover iPhone From iTunes Back up Files
How to Restore Deleted iPhone SMS from iTunes Backup