iOS 6 is finally available for public consumption, and you can get it in one of two ways: you can plug your iOS device into your computer and check iTunes for an update, or you can go into the settings menu on your iPhone (3GS, 4 or 4S), iPod touch (4G, 5G) or iPad (iPad 2 or New iPad) and navigate to General > Software Update.
While updating shouldn't wipe out your previously stored data, you should back your device up just to be safe. If you don't see the update popping up right away, you shouldn't have to wait too long. These things often do take a while to roll out to everyone.
Check back later today for a rundown on all the best features of iOS 6.