But you don't have to restore. Its a simple process of Download and Update. No technical steps to do it.
If you are running iOS 5, you can update to iOS 6 wirelessly from Settings>General>Software Update. If you are running an older version of iOS, you have to plug you iDevice into an iTunes-authorized computer and download and install the update software from there. You should be prompted there is new software available the moment iTunes recognizes your device.
By going on settings-> General-> Software Update
If you are running iOS 5, you can update to iOS 6.1.3 (or 6.1.4 on iPhone 5) by going into Setting>General>Software Update. If you are running iOS 3 or 4, you can update to the latest software by plugging your iDevice into your iTunes-authorized computer and wait for your device to be recognized. Once this is done, there should be a pop-up to download and update to the new iOS. Everything should be self explanatory by then.
If you have an iPod Touch 3rd generation, you can easily update to iOS 5.1.1 by plugging in your device to your iTunes-authorized computer and waiting for the pop up to download and update to the new software. If you are already running an earlier version of iOS 5, you can update wirelessly by going into Settings>General>Software Update. If you have a 4th generation iPod Touch, then you must update to iOS 6 because you are always forced to update to the latest iOS version available. I you have a 5th generation, you cannot downgrade to iOS 5.1 because that is not legally allowed by Apple and requires hacks.
Sync with iTunes. IOS updates will be offered when synced.
Only the iPod 4th generation can be update to iOS 6. You can update from 4.3.5 by plugging your iPod into your iTunes-authorized computer and accepting the prompt to download and install the new software.
Plug in your iPad 2 into the computer. A window will come up asking you if you want to download and update your device to IOS 5 or not. Press download and update. Depending on the amount of gigabytes on your device is how many free space you need temporarily on your computer to update.
You go on iTunes on your PC click on Software Update then download and install it
The apple iOS 5 update IS OUT NOW
You can update your 4th gen iPod Touch to iOS 6 in two ways. If you are on iOS 5, you can do it wirelessly from Settings>General>Software Update. If are running iOS 4, you have to plug your device into an iTunes-authorized computer and accept the pop-up to download and install the latest iOS software. Either way, there will be waiting involved, especially if you have a slow connection.
If you are running iOS 5, you can update wirelessly from Settings>General>Software Update. If you are running any version of iOS 3 or 4, you must plug your phone into your iTunes authorized computer and wait for the prompt to download and install the latest software.