Turn on Siri
1. Open the settings app found on your home screen or app list.
2. Click on Siri found in the settings list and toggle the feature on.
Activate Siri and issue a command
1. Press and hold the Home button. Siri is enabled by default on all devices that support it, so usually you can just press and hold the Home button to start the Siri interface. The Siri prompt will appear, and you'll be able to speak your command or question.
2. Say "Hey Siri" if your iOS device is plugged into a power outlet. When your iOS device is plugged in, you can say "Hey Siri" to launch the Siri interface without pushing any buttons.
3. Press and hold the Call button on your Bluetooth headset. If you have a Bluetooth headset, press and hold the Call button until you hear a short notification chime. You can then speak your command or question.
4. Press and hold the Voice button on your steering wheel to start Siri with CarPlay. If you're using CarPlay in your car, you can start Siri by pressing and holding the Voice button on your steering wheel. You can also press and hold the digital Home button on your CarPlay display.
5. Bring your Apple Watch up to your face to start Siri. If you use an Apple Watch, you can start Siri by bringing the watch up to your face. As soon as you raise your watch, you can start speaking the command or question.
Hey Siri is invaluable once you start using it. Answers to questions such as “What appointments do I have tomorrow?”, “Who is near me?”, and “What is the address of Felesky Flynn Calgary?” are just a small sample of what Apples Assistant can do. This link is a comprehensive list of Hey Siri commands.