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Avoid tall collars or collars with tall collar bands, as these can make the neck appear shorter.
You may want to choose a collar with slightly pointed tips, not rounded ones. V neck collars like a bishops collar, wrap necklines with a small flat collar are also good.
Go for a Kent collar for a formal elegant style. And tennis collars, polo collar for a casual style
Choose a collar with a slightly higher collar band; Other than regular shirt collars, mock turtleneck collar and bow tie collars are good choices.
Choose a flat, open collar like camp collar - the kind seen in Hawaiian shirts, short-sleeve button-ups, or even T-shirts with open necklines