Use Siri on the Apple Watch
Siri lives on the Apple Watch so you can say, "Hey Siri" or hold the Digital Crown to see your calendar, get turn-by-turn directions, text a contact, and more.
You will see the information on-screen before the message is sent and if you ask for directions you can see a map on the screen as fast as Siri works. You'll need a connection to the iPhone to make this work.
You can use many of the same Siri features as on your iPhone, but every now and then you will find that you cannot use some Siri feature without unlocking your iPhone or switching to your iPhone.
With the Apple Watch Series 3 and newer, Siri can talk back to you so you don't have to look at your Watch to see the answer.