Go to Settings > Siri & Search and make sure that "Hey Siri" and Press Home for Siri are on. You need an Internet connection through Wi-Fi or cellular data. Cellular data charges might apply.
Ask Siri a question
There are several ways to talk to Siri. You can say "Hey Siri" and ask your question. Or press the Home button, then tap the question mark in the lower, left-hand corner of the Siri screen. To see a list of what you can ask Siri, press the Home button and ask "Hey Siri, what can you do?" Learn more about what you can ask Siri.
Say, "Hey Siri"
You can use Siri without pressing the Home button. First, make sure that "Hey Siri" is on under Settings > Siri & Search > Listen for "Hey Siri." Then say "Hey Siri" and ask your question. For example, you can say "Hey Siri, how's the weather?"
If you have an iPhone 6s or later, or an iPad Pro*, you can use "Hey Siri" whenever you want. If you have an iPhone 6 or earlier, or another iPad or iPod touch model, you need to plug your device into power first.
When you say "Hey Siri," Siri determines which device you're trying to use—just make sure that Bluetooth is enabled on your devices.
Use the Home button
Hold down the Home button until Siri opens, then say what you need.
If you have an iPhone 6s or later, or an iPad Pro*, you can hold down the Home button and make your request as soon as you start holding the button. Release the button to let Siri know when you’re done. Siri responds even if Siri wasn't on the screen when you started.
Talk to Siri with your headset
If you're using a headset that has a remote or another type of Bluetooth device, hold down the center button or call button until you hear a chime. Then say what you need.
If you have AirPods, double-tap the outside of either one to activate Siri.
Talk to Siri in your car
In addition to using "Hey Siri," if your vehicle supports CarPlay or Siri Eyes Free, hold down the voice-command button on your steering wheel, then tell Siri what you need. Siri waits for you to stop talking. If you have a touch screen with CarPlay, you can also use Siri by pressing and holding the Home key on the screen. You can tap the audio-wave button to tell Siri you're done talking. This is useful if Siri can't hear you because there's background noise. Opening certain apps like Phone or Messages can also connect you to Siri.
Siri adapts its behavior depending on how you're connected. For example, if you're connected from a wired or Bluetooth headset, from Siri Eyes Free, or from CarPlay, Siri reads your messages so you can approve them before sending.
Change Siri’s voice or language
To change Siri's voice, go to Settings > Siri & Search > Siri Voice. To change Siri's language, go to Settings > Siri & Search > Language. Then choose from the list of languages that Siri speaks and understands.
To change how Siri responds, go to Settings > Siri & Search > Voice Feedback and select an option.
You can use Siri in any country or region, with any of the supported languages. Since Siri is designed to recognize accents and dialects of the supported countries or regions, Siri's accuracy rate will be highest for native speakers. Learn which Siri features are supported in which countries and regions.
Have phone calls announced
The Announce Calls feature is off by default, but you can turn it on and adjust it under Settings > Phone > Announce Calls.
You can have all incoming calls announced, only calls when you're in the car or using headphones, or only calls when you're using headphones.
* If you have an iPhone 6s or later or an iPad Pro 12.9-inch (2nd generation), iPad Pro 10.5-inch, or an iPad Pro (9.7-inch), you can use "Hey Siri" whenever you want. You can also say your request as soon as you start holding the Home button. Release the button to let Siri know when you’re done. iPad Pro 12.9-inch (1st generation) doesn't support these features.