How to update my iPhone 4s to iOS6 tho there's no Software update button?

I want to update my iPhone 4s to iOS6 but the problem is, when I go to settings > General, there's no "Software Update" Button.
I currently have iOS4 I guess and iTunes 11.1.3 on my windows PC and got no iCloud (should I have it to update?)

I tried to google tutorials for such thing but couldn't find any. Hope you can help me out

You can update it through itunes on you computer. The only problem it that you will be updating it to ios 7.0.4.

if you go to the link given, you can manually download the firmware you want and on itunes hover over "check for updates" or "update device", hold shift and left click. Once you have done that you can select the firmware you have downloaded. If that doesn't work then you can try holding shift and clicking on "restore" instead.

http://www.felixbruns.de/iPod/firmware/

hope this helps

Because your iPhone 4S is PORTABLE, this works every time:

Take it back to the store where you bought it.

And then, they will show you how to do things like this yourself. And, they can also explain iCloud to you.

Connect your iPhone to your PC/laptop > open itunes > a pop-up will appear for updates > press it and follow the instructions.