On most Android devices, you can swipe up from the Home button to get access to Google Now from any screen. However, as long as you are on the home screen you can also activate Google Now using the power of your voice. Simply speak the words ‘OK Google’.
It will then beep and prompt you to ask it something. At this point you can say ‘OK Google’ again to see a list of all the options that are possible. Examples of the commands we will cover later, but in a nutshell, anything you can type (eg ‘what is the capital of France’), you can ask! ‘OK Google, what is the capital of France?’