If you have an oval face shape, then consider yourself lucky. The goal of any look is to make the face appear as oval as possible and you already have that going for you. Oval faces should keep a soft angled eyebrow to maintain their ideal face shape, too much of an angle in your eyebrows will make your face appear longer then it is.
Long Face Shape
If you have a long face shape than your face is longer then it is wide and your chin may be pointy. Straight eyebrows with only a slight curve are going to be the best bet for this face shape. Having a flatter eyebrow is going to make your face appear shorter than it really is.
Heart Shaped Face
If you have a heart shaped face then your forehead is the widest part of your face and your chin is very pointy. The goal with this face shape is to soften your chin and balance out your forehead. The best eyebrows for this face shaped will be bold, low arched eyebrows. This will add length instead of width to the forehead and will balance out your strong chin.
Diamond Face Shape
Square Face Shape
If you have a square face then your forehead and cheeks are the same width but your jawline is going to be very strong and angular. The goal for square faces is to soften your jawline. Start with a simple curved eyebrow and then pluck it into a more angled shape. The more prominent your jawline is, the more angled your eyebrows should be.
Round Face Shape
If you have a round face shape than your face is almost as long as it is wide and your cheeks are the widest part of your face. The goal for this face shape is to make your face appear longer. To do this you should avoid rounded eyebrows and instead opt for more angled brows that will create vertical lines to give your face more of an oval look.