If you are going to click the little tree icon up there ^ then you need the direct link. You can also adjust the dimemsions there (I just learned that yesterday)
You can also just use the IMG Code and paste that into the post, but you can't adjust the size.
My boss came up in the middle of typing this, so I'm sure someone has already beat me to these instructions, but I've already put too much effort into this post to delete 