If you want to put a Youtube video on your profile, then all you have to do is:
1. Go to User Control Panel
2. Edit Your Details
3. Scroll down to "Youtube URL" under Additional Information
From here, you only enter the value from the URL. For example, v=hBcXe2B97TQ.
You change the equal sign to a '/' so you should now have something like this: v/hBcXe2B97TQ
After that, you save your changes, and the video should be successfully added to your profile. You can also add the video title and your choice of quality right under the portion where you entered the URL.