Placing a hat on the bed is, apparently, bad luck. (South Carolina)
9
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
Some motorcycle enthusiasts hang a biker's bell from a portion of their bike to protect themselves from evil road spirits.
64
Once a wedding ring has been placed on the finger, it is considered bad luck to remove it.
117
If you catch a falling leaf on the first day of autumn you will not catch a cold all winter.
394
In some parts of England, rum is used to wash a baby's head for good luck.
71
An acorn at the window will keep lightning out
93