Start by placing a few bats to the side of the door frame. Keep adding more according to the size of bat - place all of the large sized bats first then the next size down and so on.

Keep adding more according to the size of bat - place all of the large sized bats first then the next size down and so on.

Create a cluster effect and stick a few bats inside the door frame.

Add as many as you like - they can be escaping from a room like or they can be swarming through your window.