Let's just say you want to post the a team by Ed sheeran
So just type it in and click on the video after the + sign click the button after it and you should see copy link at the bottom click it and then come back to GAG and right click to press paste and it will post the video up. http://youtu.be/UAWcs5H-qgQ
There is a 3 limit of posting videos directly on here and then they'll just post the link after that and if you post it on your coment or someone else's coment the link will only appear and it will tak you to YouTube instead.
Simply copy and paste the URL address of the video or image into your question's details or your opinion. After you've submitted your post, the system will embed it for you. Images and videos will only embed in a question's details or in an opinion, never in a question update. Also, you can only post 10 clickable links per post (3 will embed, the rest will appear as links)! If you're wanting to embed your own photo, you'll need to first upload that photo to an image sharing site like imgur or photobucket, then use the link they give you for the image.
Please remember, nothing explicit or offensive! Keep it relatively clean, guys!