First --> open your youtube on your browser then open your video And copy URL.
Then-->Run your vlc
Then click Media->open network stream..
Third -->Then paste URL in 'please enter network URL: '
--> Then click ' Play' button in the player.
--> Then Now, click Tools – Codec Information and at the bottom of the window you will see a Location box.
Copy the long URL in the box and paste it on your browser’s address bar.The browser will now start playing the video file.You can download the video file to your desktop by doing a Save As…. Or you can choose to record the video.