Well, I don't know if you want the iOS 7.0 update on your iPhone to go away or you want iTunes to stop telling you that there is an update available for you every time you connect to the computer?
Then you might mean that you downloaded iOS 7.0 firmware update and its now installed on iPhone. If that is the case, Apple has stopped signing iOS 6.1.4 and because of that, unless you have an iPhone 4, you are stuck with iOS 7! Unless Apple for some reason or another starts signing iOS 6.1 firmware again like back in July, will never happen again.
Since I really don't understand your question, maybe I should ask you as to why you don't want the update anymore, is it to jailbreak your iPhone? It's probably the user interface is too much of a change for you.
If you really don't want the update anymore, my only suggestion for you is to try and trade or sell your phone for a iPhone 4S with an older firmware installed. Good luck and I hope that, if by a small chance, something that I wrote can truely help you out then I did my job!
the only way you can do this is to have a jail broken phone, the perks with a jailbreak phone is you have the ability to switch to different ios versions whenever you want.
and the bad thing about this is, if you jailbroke your phone when it was ios 5 you can only jump between that point and up, back and forth in your situation if you were able to jail break now you will be stuck at 7 as a starting point unable to go backwards.