The importance of ear placement is absolutely vital to your finished doll. No matter how well you've sculpted your doll head, if you've set the ears either too high or too low, the finished head will always look somehow unnatural.
Here's how I've shown my seminar students to find the correct placement of both ears evenly on their doll heads. You will also find this method on my Magic Skin Video.
You start by finding the hinge. Place your fingers just in front of the opening of your own ears and chew several times. You should be able to feel where your lower jaw meets your upper cheek bone. This is the hinge and the ear hole is right in back of that.
Now take two toothpicks and place them right where that hole should be on your doll's head. Next and most importantly, we have to check for symmetry. To do this, you must look closely at the doll from all angles. First face forward to be sure one toothpick is not higher than the other. Next look straight down on the doll head, moving it slowly from top to bottom while looking carefully to see if one pick is more forward on the face than the other. You might even want to look at your head in the mirror for another perspective.
You will probably find the first few times you do this, that you may have placed the toothpicks a little off. However, using this method and with a little practice you should be able to get them to exactly the right spot on each side. Once you are satisfied that your toothpicks are aligned correctly, you can remove them and form the clay around the hole and continue making the ear as I show you in my Magic Skin Video.
Good luck to all of you with your doll making!