I found this story on the "History of the 18th and 19th Centuries" blog here. A list of primary sources can be found at the bottom of this post.
While their blog post goes into far more depth and is definitely worth a read, I'm just going to bullet-point the crazy and put my snark in brackets:
Things that cause bad luck:
–If thirteen people sit down to table together, one will die before a year has passed. [Anyone who has read Harry Potter will be familiar with this one. And in Rowling's universe, that shit is TRUE].
–Three candles burning at the same time in a room denotes death. [Or the week before Christmas on an advent wreath. Or the third night of Hanukkah. Or that you've run out of candles for you candlestick.]
–The ticking of [an] insect [is] called the death-watch. [Great to know the name for it. Doesn't make it a superstition.]
–Seeing the new moon for the first time through glass is unlucky. [This is why I sleep outside once a month. Well, that, and the fact that I'm a werewolf and will be outside anyway.]
–Two knives falling across each other is unlucky.
–Being "overlooked", which was the same thing as giving someone the evil eye, a malevolent look that brought bad luck or injury. [Guys, if it were possible to dirty-look someone to death, there would not be a single preteen with wheelie sneakers left alive.]
–If you're in Ireland, don't disturb or dig up a fairy community. It's will end in your total destruction. [I think there's a similar rule in Miami.]
–Don't sneeze. [Apparently EVER.]
Things that prevent bad luck [hint: it's just spitting on everything]:
–You should spit every time you see a white horse, a squinting man, or a single magpie, or if you step on a ladder, or wash your hands in the same basin with a friend. [White horses in the UK must have such a complex.]
–You shold spit on your fingers before getting into a fight. [Because it's so gross, the other person will probably back out.]
–Travellers should spit when they leave home.
–Market people shold spit on the first money they recieve. [which is SUPER sanitary for people working with food.]
Now for the "medical cures!" (hint: they all involve doing something random three times in a row)
–Rickets in children can be cured by splitting a young ash tree with a three foot incision and passing a child through the tree three times. Then the child must be washed for three successive mornings in the dew from the leaves of that tree. [Or, you know, feeding the kid. That works, too].
–Whooping cough in children can be cured by passing the child in a full circle three times around the torso of a three-year-old donkey. Then you would pull three hairs from the donkey and boiled them in three tablespoons onf milk and fed it to the sick child for three consecutive mornings. [Hoola-hooping a donkey and drinking its hair: just like they taught me in medical school.]
–If your child sneezes, they are no longer under a fairy's spell. [What happened to never sneezing ever?]
According to the blog, "sometimes, a person's luck depended on the day they sneezed, as indicated by the following poem:
Sneeze on Monday, you sneeze for danger;
Sneeze on Tuesday, you kiss a stranger;
Sneeze on Wednesday, you sneeze for a letter;
Sneeze on Thursday for something better;
Sneeze on Friday, you'll sneeze for sorrow;
Sneeze on Saturday, your sweetheart to-morrow;
Sneeze on a Sunday your safety seek,
The devil will have you the rest of the week!"
Godey's Magazine, Vol. 92, 1876, on Google Books
"Horrible Superstition," in Morning Post, pg. 4, 31 July 1826, by subscription on The British Newspaper Archive
"Rural Superstitions," in Exeter and Plymouth Gazette, pg. 4, 3 October 1845, by subscription on The British Newspaper Archive
"Superstition," in Aberdeen Evening Express, pg. 4, 7 May 1879, by subscription on The British Newspaper Archive
"Superstitions of Ireland," in Cambridge Chronicle and Journal, pg. 4, 23 January 1824, by subscription on The British Newspaper Archive
Walsh, William Shepard, eds., etal., American Notes and Queries, Vol. 6, 1891, on Google Books
Warner, Richard, An History of the Abbey of Glaston, 1826, on Google Books