1. Open the notification menu using the button in the bottom right (highlighted in red circle), then scroll down till you see the notification regarding “Encryption needed” and select it.
2. Select "you have no other encryption software installed".
3. Select the top option “Save to your Cloud domain account”, it will then notify you at the top saying “Your recovery key has been saved” and then select next.
4. Select the second option to “Encrypt entire drive”
5. Select option one for “New encryption mode”
6. Finally, select “Start encrypting”