1. Launch
Hit the search button to launch Cortana (or choose the Tile or Cortana from the app menu)
2. Menu
From the upper left split-view menu, choose Notebook
3. Settings
In the top area of the Notebook select Settings
4. Enable
From the menu items listed enable Hey Cortana.
Addtional Functions
You also have the secondary option to train Cortana to recognize just your voice or anyone.
To train for your voice select To me and the program will walk you through the steps to learn your manner of speaking.
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