To automate a text reply in twilio for an unmonitored phone

Log in to Twilio
Click on the #
Click on the number you want an automatic response for
Scroll down to messaging
Scroll down to "a message comes in"
Choose web hook
Fill in the next box with something like:

http://twimlets.com/echo?Twiml=%3CResponse%3E%0A%3CMessage%3E%0AThis%20phone%20number%20is%20not%20monitored.%20Please%20contact%20the%20office%20of%20Dr.%20Robertson%20at%20604-846-4477%0A%3C%2FMessage%3E%0A%3C%2FResponse%3E&

Choose HTTP Post