Install ios12
ios12 profile
iPhone 4S, iOS 9.3.5
ios12 profile
iPhone 4S, iOS 9.3.5
iOS 12 is not yet available for official release. I don't believe iOS 12 is even available in Beta. If history repeats, we can expect to learn officially about iOS 12 in June, with official release prior to the release of the 2018 iPhone lineup in September.
Are you wanting to install IOS 12? You would need to join the Beta Program. If that isn't what you want, more information would help.
Install ios12