This quick tutorial illustrates how to draw anime and manga ears from the side, front and back views.
Anime and manga ears vary in styles from more realistic to very simplified but there really is not one defining way to draw them.
It is also difficult to have clear guidelines for drawing ears in general because of their irregular shape. One good thing to do is to simply look at some examples as shown in this tutorial or at photos of real ears if you are going for a more realistic style.
When drawing anime ear from the side view it may be helpful to think of it as an oval or an egg that is tilted to one side.
More realistic/serious anime styles tend to draw the ear closer to traditional art while more cartoony styles often simplify the ears to the basic shapes mentioned above.
The distance of the character also makes a difference when drawing the ears. If you are drawing a character that is standing in the background of the picture or off in the distance you may not need to draw any of the inner parts of the ear at all and only outline the overall shape.
Placement of the Ears on the Head
For horizontal placement draw the top of the ears close to the bottom of the forehead and the bottom of the ears close to the tip of the nose.
For vertical placement draw a line down the middle of the head and draw the ear just a little bit to the side of that line.