Before embedding a video on your site, upload the video to YouTube. Ensure that your video isn't set to private on your host's page, as only public videos will render properly on your site. Click this link for their instructions.
Once the video is hosted on YouTube, you can embed it in any pages or side bar of your site using a URL.
To embed your YouTube videos, channel or playlist in the sidebar of your site, simply add a YouTube widget in the back-end of your site at Profile > Pages > Sidebar.
Choose YouTube, name the feature and add the URL of any YouTube video, channel or playlist you wish to display.