To get the proportions right when drawing a koala, it's important to pay close attention to the size and placement of each feature. Start with a light sketch of the basic shapes - the head, body, arms, and legs - before adding in the details. Pay attention to the size of the head with the body, and the length and thickness of the limbs. The ears and nose are also important features to get right, as they help give the koala its characteristic look. Remember to take your time and adjust as necessary until the proportions look just right!