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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Two people breaking a wishbone is said to lead to good luck for the person with the larger piece.
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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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In Asia, the digit 4 never appears in any Nokia handset model number, because 4 is considered unlucky in many parts of Southeast/East Asia.
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Placing a hat on the bed is, apparently, bad luck. (South Carolina)
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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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Placing keys on a table is considered unlucky. (Sweden)
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