How to draw a football (Soccerball)

I need to draw a 3D (style) football.  I've seen pictures on the web so I know it can be done.

The white segments are hexagons and the black are pentagons as in the attached picture.  Of course, these won't match up correctly whilst lying flat as a football is round.  How do I create the illusion of this? And the shading etc?

Thanks in advance for ANY help! I've no idea where to start!

SamanthaJane