I do know how to sync my iphone to my computer?

I want to sync my data from my iphone to my computer. I had an old itune in my computer which is empty now. I'm afraid if I sync my phone to the empty library of my computer, it will erase my phone. That happened to me once and I lost my mind over my lost data
would you please tell me how can I transfer my phone info to my computer?
the home button and sleep button of my 4G stopped working and I'm so worry about my data

Hi, you can use 4Videosoft iPhone Transfer Platinum. It can help you transfer your iPhone files to computer without loss them. And it can also help you backup the SMS and Contacts. Hope it can help you.