You have to find the graphic online somewhere, it can be on someone's fubar photos, or anywhere on the internet.
Right click the image and copy image URL.
HTML tags are always between the Greater Than "<" and Less Than ">" Symbols.
To make an image appear, use the tag "<img src=" which stands for Image Source
Then place the URL within double quotes " " and finish with the less than character.
For instance, the animated gif of the double pie to the face looks like.
<img src="http://stream1.gifsoup.com/view7/2764069/girl-pied-in-face-o.gif">