Opening an umbrella indoors is said to result in 21 days of bad luck. Some traditions hold that it is only bad luck if the umbrella is placed over the head of someone while indoors.
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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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Breaking a mirror is said to bring bad luck for 7 years. To "undo" this, take the shards of glass and bury them underneath the moonlight. In ancient times, the mirror was said to be a window to the viewer's soul. If that mirror were to break, it would
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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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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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Before traveling a person should, apparently, sit on their luggage. (Russian)
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Placing a hat on the bed is, apparently, bad luck. (South Carolina)
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An acorn should be carried to bring luck and ensure a long life.
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