Two people breaking a wishbone is said to lead to good luck for the person with the larger piece.
225
Placing a hat on the bed is, apparently, bad luck. (South Carolina)
9
There are numerous sailors' superstitions, such as: it is considered bad luck for a ship to set sail on a Friday, to bring anything blue aboard, to stick a knife into the deck, to leave a hatch cover upside-down, to say "pig", or to eat walnuts aboard.
70
In some parts of England, rum is used to wash a baby's head for good luck.
71
It's bad luck to leave a house through a different door than the one used to come into it.
143
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)
463
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
If you catch a falling leaf on the first day of autumn you will not catch a cold all winter.
394