Somebody with a round face, you have to be very careful not to cut the hair too short in the back. It emphasizes the roundness of the face; it's always nice to see a little neck from the back when you are looking at somebody. It should frame a little more around the face, and short blunt haircuts look good. A medieval type of look is not a very good look for somebody with a round face.
Long faces:
For somebody with a skinny and long face, a short bob is not good. It elongates the face. Basically, what you have to do is you have to take all of that into consideration when you are doing your haircut; the shaping of the face and the texture of the hair. There are all these variables when you are doing hair. I recommend leaving bangs longer when somebody has a long face, because it makes the face look shorter. Short bangs are pretty bad for a long face. Having a short side with a long back is very bad for long face types. Sometimes people have expectations of a haircut, and if you show them pictures of people with long faces and the wrong haircuts, then you win-over the client. That's why the consultation is so important.
Heart shaped faces:
If they have a heart shaped face, they have more choices really. They have more choices, because the face is not really round or too skinny. They really could wear it more ways.
