1.) From YouTube, get the full URL for the video. (example: https://www.youtube.com/embed/blah-blah-blah)
2.) Insert an image into your article that will be the thumbnail image that the web visitor will click to open the video. OR... type a label like "Click here to view the video"
3.) Wrap the image tag or the text from step #2 with the modal plugin. Note where you should insert the real YouTube URL.
{modal url="https://www.youtube.com/embed/blah-blah-blah" width="560" height="315" title="Title of it"}<img class="img-responsive" src="images/alliance-forte/sikich-marketing-videography.png" alt="" width="400" height="232" />{/modal}
4.) Save the article.
5.) Refresh the public page to test.
More information is available at Regular Labs web site: