The article provides a step-by-step guide on how to use the csh shell to make a phone call from a new Twilio number using the Twilio API. To start, you need to set your Twilio credentials in the csh shell by substituting the account SID and auth token variables with the actual values from the Twilio console. Then, you can query Twilio's REST API to find an available phone number using cURL and sed commands. Once you have an available number, you can purchase it and add it to your account. Finally, you can use a sample TwiML script to make a phone call using the Twilio API, which will play a message from Alice and some relaxing music. The guide is useful for prototyping or adding features to production scripts and provides a useful skill for anyone working with Twilio.