To post the video, not just the link,
Copy the video url at the top of the page, w ww.whatever,
back at the 'fire, in the reply bow, select "Switch to Full Screen Reply"
select the 5th icon from the left, the blue TV, select youtube and past the link there.
Preview to be sure you got what you want and submit!

Doing it is easier than typing it.

"Camping places fix themselves in your mind as if you had spent long periods of your life in them.
You will remember a curve of your wagon track in the grass of the plain like the features of a friend."
Isak Dinesen