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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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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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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Once a wedding ring has been placed on the finger, it is considered bad luck to remove it.
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Amber beads, worn as a necklace, can protect against illness or cure colds.
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An acorn should be carried to bring luck and ensure a long life.
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Before traveling a person should, apparently, sit on their luggage. (Russian)
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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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