To use Pinboard 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 Pinboard to query the data you need using the URLs you provide, for example: you can create bookmarks in Pinboard by sending a POST request to the appropriate API endpoint with the necessary parameters, such as the URL and description. To update existing bookmarks, you can utilize the same HTTP Request node with a PUT request, which allows you to modify the bookmark details by specifying the unique URL. For retrieving data, simply use a GET request to pull bookmarks or tags based on your specific requirements, giving you full control over the data you access.