The first step, when you start to draw a head, that you choose the view of the head. Here, you can find some example, and you can choose, what do you want. And you must draw the bird-, and frog perspective in foreshorten. (What is closer for you, you must draw bigger, what more far from you, you must draw smaller.)
*Tip: For the face shape types please, look my "How to draw pretty girls" tutorial, you can find this part as Step 3. And in the Step 4. you find a short info about the face's symmetry too.