How to install ios 7 on iphone 4s 6.1.3?

Everything ios 7 i have installed for my iphone 4s 6.1.3 is not working with the shift and check for update button.

IOS 7 is not yet available. It is currently being tested by developers to make sure their apps are working correctly with it. The finished version of iOS 7 will be available from Software Update on your iPhone in a few weeks.

https://developer.apple.com/....com/ios7/

You won't be able to install iOS 7 yet unless you register your device's UDID with a developer account through a site like http://www.udid.in/.It's $5, and then you can try out the new OS before everyone else and don't need to worry about Apple disabling your device for running unreleased software.