In a detailed walkthrough, the process of using Postman and AssemblyAI for speech-to-text transcription without writing any code is explained. By leveraging Postman, a versatile API testing tool, users can upload local audio files to AssemblyAI, which is an API-based transcription service, and receive a URL for the uploaded file. The guide outlines how to configure HTTP requests in Postman to first upload an audio file and then request its transcription by using the URL provided by AssemblyAI. The transcription process includes the option to enable advanced features such as speaker labels and PII redaction. Once the transcription is processed, users can retrieve it by making a GET request with the transcription ID. This method provides a quick and efficient way to utilize AssemblyAI's transcription services, demonstrating how API collections can be shared among teams depending on the Postman licensing tier.