To send a WhatsApp message in 30 seconds using JavaScript, you'll need to set up a development environment with Node.js and npm, create a new directory, initialize a new Node.js project, install required packages, and configure your Twilio account. You'll then write code that uses the Twilio library to load your account SID and auth token from environment variables, create a message with a body, and send it to a WhatsApp number. After running the code, you'll receive a success message in your command line and a WhatsApp message with the sent text, allowing you to expand your skills by trying out other tutorials and projects.