Then draw this. Remember, the chin lines really are just two triangles missing the bottom. They can be done at any angle so desired. Also, the center line can be as long or short as you choose. Just don't make it TOO long, or else you'll have a horse-person!
Draw these lines. They tell you where to put the face.
Line 3 is where the nose should be. In between lines 1 & 2, that's where you put the eyes. I won't draw them in, because that's up to the artist, and I'm not you.
Line 4 is where you put the mouth. The center line should stay until you've drawn the mouth, to help you MAKE IT EVEN, or, if you're doing a crooked smile, you can erase it.
In the end you should have something like this. Oh, and please forgive the basicness of this tutorial. I did it on paint. NOT RECOMMENDED!!!!!