Pour some white paint into a reusable plate to make it easier to access.
On the coloured card make a large circle for the polar bears face by dipping the pom pom into white paint and then dabbing it on to the card.
Make two smaller circles at the top to make the polar bear's ears. You could use different sized pom poms for this if you liked.
Using the pom pom 'colour in' the polar bear by filling his face with paint using the pom poms dabbed in the white paint.
Glue on googly eyes for your polar bear.
To make the polar bears mouth either cut a triangular shape and mouth shape from black card and glue these on - the cutting will likely need to be done by a grown up if you are making this with a toddler, or wait until the paint is dry and draw the polar bear's features on with a black marker pen.