I see many posts with a link to YouTube which makes a member leave the forum to view . The forum and YouTube have the ability to bring the video here and will make your post look that much better.
While at YouTube click on the share link, right click on link to open menu screen, left click on copy. You now have the link to bring here.
Now to insert it in your post.
First click on the film icon . Next on the window that opens click on the box. Right click and drop down window open. Left click on "paste". The Youtube link is now in the box. Click "OK" and then the YouTube link is in your post.