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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An acorn should be carried to bring luck and ensure a long life.
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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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Two people breaking a wishbone is said to lead to good luck for the person with the larger piece.
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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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Placing a hat on the bed is, apparently, bad luck. (South Carolina)
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It's bad luck to leave a house through a different door than the one used to come into it.
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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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