it's in settings

Just hover your pointer over your username in the top right of the screen and click "Settings" in the drop-down menu that appears. There's a field where you can paste the URL of a youtube (or Vimeo, I think) video. Once you do that, the "Embed Youtube[/Vimeo]" button should appear next to it. Did that make sense?

edit: sniped lol

Hover over the arrow, click 'Settings'



Paste the link in the spot for it