Sending an SMS with PHP can be achieved in under 30 seconds using Twilio's APIs. To start, you need to install the required dependencies and set up environment variables for your Twilio account, recipient mobile number, and sender ID. Then, write the PHP code that creates a new Twilio Client object and uses its create() method to send an SMS with a predefined message body. The code is tested by running it through a terminal command, resulting in a confirmation message being printed to the terminal and an SMS being sent to the recipient's mobile number. While this tutorial covers the basics, there are many more features available for sending SMS with Twilio, including tracking delivery and scheduling messages for later sending.