It was once said that oval was the only face shape to have. Those days are long gone and diversity is what makes a woman beautiful.
Tip: If you are curious about the shape of your face the simplest way to find out is to pull all of your hair back and while looking in the mirror outline your reflection with lipstick lightly.
All cuts do not necessarily suite all people. In addition to your personal style and hair type, your face shape has a lot to do with the cut you choose. Here are some simple guidelines.
ROUND

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This shape is even through the eye, cheek and upper jaw area. A fringe can work as long as they are longer with a side sweep. A full fringe will shorten your face while widening the sides; a no no for this face type. Layers that swing out all over are also not recommended as they trick the eye outward. You want the eye to look down, not out. Instead, try layers that add a bit of volume and are a bit wispy towards the ends.
SQUARE

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This shape is quite similar to round, with a stronger jaw and forehead area.If you like a shorter look, ensure your stylist adds body from the ears up tapering the cut slightly toward the ends. A longer bob with distressed ends would be a good choice as it would add a bit of volume on top and give a flattering narrowing look down past the jaw line. Longer hair can really flatter this face shape.
OVAL

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This face is balanced allowing for a greater variation of looks. At one point this was the face shape to have, though modern ideas of beauty allows for so many variations on this. Almost any cut can work with this shape.
RECTANGLE

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This shape is similar to oval but longer and with stronger lines. It can tend to pull slightly long and narrow at times. Centre parts will give the illusion of length and are not a good idea for this face shape. If you like your hair a bit longer, volume or a bit of a wave is a good idea. If you like it shorter a fringe is perfect no matter what style you chose. Having a stronger jaw line is actually a good thing with a bit of soft layers around the upper areas of the face.
DIAMOND

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This shape is widest in the cheekbone area. A fringe can work well to balance the wider cheekbone as will soft broken layers around the jaw. Avoid cuts that are wide at cheek area and end too far above the jaw line. Most women would kill for amazing cheekbones so consider yourself blessed.
HEART

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A heart shape is wider at the forehead vs. the jaw line. Depending on how narrow the jaw line is this face can carry a straight fringe. A bit of a side sweep will always work. A cut that swings out a bit helps to balance the jaw area vs. one that narrows down tightly.
TRIANGLE

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T
his shape is wider at the jaw line vs. the forehead. Avoid cuts that are shorter than your jaw, as this will give a wider finish. It is best to keep away from any cuts that mimic your face shape, longer layers that lay softly around the face will look better than layers that flip out, adding the illusion of width.