To send an RCS message with Twilio and Python, you need a Twilio account, a phone number for sending SMS as a fallback to your RCS service, a device capable of receiving RCS business messages, and Python installed on your machine. You can create an RCS sender in the Twilio Console, add profile information such as a name, description, logo, banner, contact details, and link to privacy policy and terms of service. After setting up your RCS sender, you need to test it by sending a message to yourself or another device. Once verified, you can create a messaging service in the Console, add your RCS sender, and set up an SMS fallback sender. You also have the option to set up webhook integration for handling incoming messages. To send your first RCS message with Python, you need to copy the Messaging Service SID, retrieve your Account SID and Auth Token from the Twilio Console, create a new file named `send_rcs.py`, run the script using `python send_rcs.py`, and see the result on your phone or device. With Twilio, you can explore advanced RCS features such as content template builder for rich message content, programmable messaging logs to troubleshoot errors, and secure one-time passwords with Twilio Verify.