Draw and cut out some eyes, noses and mouths. You could also cut face parts out of magazines.
When you are drawing eyes, think about different colors of irises (the colored part of your eye), different shapes, closed, open, winking, animal, human, alien, enormous, tiny, long curly eyelashes, wearing rainbow eyeshadow or glasses… any kind of eyes!
When you are drawing noses, try out different shapes, sizes and colors. Triangles, circles, nostrils, no nostrils…pig noses are especially cute and easy to draw.
When you are drawing mouths, try out expressions and looks of all sorts: toothy grins, shy smiles, grouchy mouths, teeth with braces, mouths missing teeth, mouths with fangs, pointy beaks, long tongues sticking out.