When you speak of bad luck, it is said that one should always knock on wood. Also knocking when speaking of good luck apparently helps with having good luck. This is an old Celtic tradition related to belief of wood spirits.
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If you catch a falling leaf on the first day of autumn you will not catch a cold all winter.
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If one walks underneath an open ladder it is said to bring bad luck. Sometimes it is said that this can be undone by immediately walking backwards back underneath the ladder.
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In some parts of England, rum is used to wash a baby's head for good luck.
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Once a wedding ring has been placed on the finger, it is considered bad luck to remove it.
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Many believe that if all of the candles on a birthday cake are blown out with one breath, while making a silent wish, the wish will come true.
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Placing a hat on the bed is, apparently, bad luck. (South Carolina)
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Collect seven or nine different flowers on midsummer eve and place them under your pillow and it is said that you will dream of your future spouse. (Sweden)
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