To use Relink - URL Shortener 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 Relink - URL Shortener to query the data you need using the URLs you provide, for example: after setting up the HTTP Request node, you can create a new short URL by making a POST request to the Relink API endpoint with the original URL in the body. To retrieve details of a shortened URL, use a GET request with the short link appended to the endpoint. Additionally, if you need to update or delete a short URL, you can do so using PUT and DELETE requests respectively, specifying the short URL in the request.