Start whith the haed. Make it simple and leave a litle spase under the nose for the tail.
Next draw the back. It's a long line which is thin at the ends and larger at the midle.
Finaly make the tail. It has to be big, cuz it's the unique sign of the fox. Don't forget to draw the line between the orange and the white of the tail, when you do it, there will be no doubt that it's a fox =) .