The tutorial explains how to receive images sent by users on WhatsApp using Django and Twilio. To start, the user needs to create a new Django project and install the necessary dependencies, including Twilio's Python Helper library, requests package, and Pyngrok. The user then sets up a WhatsApp sandbox account and connects their smartphone to it. Next, they configure the Django project to use ngrok to make the local server accessible over the internet. A webhook is created using Twilio's concept of webhooks, which allows the application to perform custom actions in response to external events such as receiving a message from a user on WhatsApp. The user updates the logic inside the message endpoint to extract information about the incoming message and saves the image locally. Finally, they send a response back to the user through WhatsApp using TwiML. To complete the setup, the user configures the WhatsApp webhook in the Twilio console and tests it by sending a message to the sandbox number.