Well this is very easy. You can do this on your iPod Touch too. All you need to do is make sure your device is running iOS 4.2.
(You can check this by tapping Settings > General > About and having a look at which version you are running).
If you are on 4.1 or lower, you will not be able to print. To print you need to update your iPhone or iPad via iTunes.
Please leave a comment if you know of another way without ‘jailbreaking’ your iPhone or iPad. Alternatively if you have found this information useful please share this with your friends. Thanks.