Once you're on the page of your selected video, go to the top of the page and hit "captions." You can either write the transcript on your home computer and upload the file to YouTube, or you can just enter the text on the YouTube website. You will also need to enter a "track name." Either way, make sure your keyword phrase is the first words you enter, and also have your keywords as the last words that are entered. Once again, this will help the search engines find your video. Click "done," and that's it.