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.
208
It is bad luck to put new shoes on a bed (or a table) (comes from the tradition of dressing a corpse in new clothes and shoes and laying them out so everyone can give their respects) - (UK)
57
Placing keys on a table is considered unlucky. (Sweden)
3
Before traveling a person should, apparently, sit on their luggage. (Russian)
117
In some parts of England, rum is used to wash a baby's head for good luck.
71
Placing a hat on the bed is, apparently, bad luck. (South Carolina)
9
According to an age old custom, carrying a dead shrew in your pocket wards off rheumatism!
24
If you catch a falling leaf on the first day of autumn you will not catch a cold all winter.
394