It's the same shape as a bowling pin
Add some eyes to your bowling pin by drawing two ovals in the top part and two coloured in ovals inside those
Below the eyes, draw a long upside-down tear drop. It also looks a bit like a carrot
Draw two slightly pointed ovals on either side of the body
Give your penguin something to stand on by drawing a couple of extended W's at the bottom of the body
Draw in a semi-circle in the lower part of the body and two more semi-circles either side of the beak for that classic penguin look
Colour the body and flippers in and you're done!
(Penguins are usually black and white, but you could try other colours. Like green. Green's a nice colour.)