Start off with 2 slightly curved upside down V's. Draw a thin, pointy oval in each to make the inner ear bit.
Next add a straight line to join the ears at the top and a big round line to join them at the bottom
Draw 2 circles in the face space and another couple of filled in circles inside them
Between the eyes, add a pointed semi-circle and a couple of lines or dots for nostrils
Draw in a big curve for the mouth and don't forget to add in a couple of triangle fangs for biting
Give your bat a fluffy oval shaped body under its head
Draw a big curved line from the head pointing to the night sky, then loop back round to the bottom of the body with an upside-down wave shape. Do the same on the other side to prevent your bat from flying in circles.
Finally draw a very thin triangle from the bottom of the body and add a flap either side with a slightly curved line connecting to the wings