If you want to jailbreak your iDevice or downgrade to earlier firmware you have to enter in DFU mode
(It is different from the Recovery Mode!)
So let’s enter in DFU!
- Press and hold the Power Button for 3 seconds
- Don’t release the Power Button and press the Home Button (Bottom-Middle Button) for 10 secs
- Release the Power Button and keep holding the Home Button for 15 seconds
That’s it! You entered in DFU Mode! Now your screen should be black. If the iTunes logo appears you have entered in Recovery Mode (To exit recovery use TinyUmbrella)