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
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.
105
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.
75
Before traveling a person should, apparently, sit on their luggage. (Russian)
117
It's bad luck to leave a house through a different door than the one used to come into it.
143
Placing a hat on the bed is, apparently, bad luck. (South Carolina)
9
An acorn at the window will keep lightning out
93
Once a wedding ring has been placed on the finger, it is considered bad luck to remove it.
117