it’s important to think of ears as having 3D volume, and not just being flat bits sticking off the head. it can help to visualize ears as stretchy cups, with a rim and a base. from there you can more easily imagine how their shape distorts as they move in space.

also, don’t forget that the ridges or fur lining of an ear follows the inner curve of the ‘cup’, and can be a great way of further indicating that volume.