To use MoonMail integration in n8n, start by adding the HTTP Request node to your workflow canvas and authenticate it using a generic authentication method. Once connected, you can make custom API calls to MoonMail to query the data you need using the URLs you provide, for example: you can create new users in MoonMail by sending a POST request to the appropriate endpoint with the required user data in the body. For example, to update a user's subscription status, you would use a PATCH request, including the necessary payload. To retrieve campaign data, simply send a GET request to the campaigns endpoint, allowing you to pull the latest information for analysis or reporting.