Make sure to select MP3 as the output format. 4 Select the Output Format: Some YTMP3 converters may offer different output formats, but MP3 is the most common choice for audio files.The converter will initiate the process of extracting the audio from the video. 3 Start the Conversion Process: After pasting the YouTube URL, click on the 'Convert' or 'Start' button.Right-click in the text box and select 'Paste. 2 Paste the YouTube URL: You will usually find a text box where you can paste the YouTube video URL.Simply copy the URL of the video from the address bar. 1 Find the YouTube Video: Begin by locating the YouTube video from which you wish to extract the audio.Here's a step-by-step manual on the way to use it effectively: Using a YTMP3 converter is generally a straightforward process. How to Convert Youtube to MP3: Step-by-Step Instructions