Head into the video manager, and find the video you want, and hit the edit button on it. In the Info + Setting thing, look down for the box labled "Private, click the drop box on it, and select either unlisted or public so those can see. If you want the video only to be seen by a selected amount of people, set the video to unlisted, that way, only people with the link may see. Though It's your choice, and there's a few other ways you can try out.
