You can find the Twilio button in the header of a Job Detail screen
after opening a job:
Clicking on Customer Number will populate the Phone Number
field with the customers Mobile Phone. In the Text Message field you can write
your message and then you can click Send to send the text. Text messages sent
are also saved to the Job Notes.
Use Saved Message will populate the Text Message field with
a saved message that can be edited from the Main Menu > Settings > Twilio.