1. Candles on Halloween
If a candle flame ever turns blue on Halloween, a ghost is nearby. If a flame ever goes out by itself, a ghost has come to call.

2. Jack O' Lanterns
Everybody knows that candles in Jack O' Lanterns are meant to keep spirits at bay, but if you gaze into the flame, you can peer into your future. It works best if you burn a new orange candle from midnight to sunrise, and it'll give you good luck. However, if you burn a Halloween candle at any other time of year, bad things will happen to you that you can't control.
3. Seeing your future husband and children
A girl who carries a broken egg in a glass to a stream can catch a glimpse of her future husband and children if she mixes some of the spring water in the glass on the day of Halloween. That night, she must return to the stream with a lamp and she'll be able to see her future husband's reflection. Another legend involves a girl emersing herself in a dark room with a single candle as her only source of light. She must place the candle in front of a mirror and peer into it while either eating an apple or combing her hair. After a few moments, the face of her future husband will appear over her shoulder.
4. Omens of Death
If you hear footseps behind you on Halloween night, don't look back because it could be Death himself. Staring Death in the face is sure to hasten your own demise according to ancient folklore. It's also said that if you cast a headless shadow or no shadow at all, you will die within a year.
5. Bats
If a bat flies around your house three times on Halloween night, it is foretelling a death. If it flies into your house, a ghost is approaching (or maybe the ghost let it in). However, if bats come out early and start flying around playfully, it's asign of good weather in the near future.
6. Warding off ghosts and evil spirits
Bury animal bones or place a picture of a beloved animal near every doorway of your house. This is said to keep unfriendly entities out.
(Note: For all the stupid people out there, I am not suggesting you to kill an animal and bury it. If you do, my legion of flesh-eating pixies will hunt you down and eat you from the inside out.)
7. Spiders
If you see a spider on Halloween, don't kill it!!! It just might be the spirit of a departed loved one watching over you.
8. Bonfires
It is a Celtic tradition to have bonfires every Halloween. Once the fire was burnt out, a member from each family that helped build the fire would place a small stone within the circle of ashes. The next day, if any stones were displaced or damaged, it was believed that the owner of the stone would die within a year.
9. Lighting the Witches
In Lancashire, people used to carry candles from eleven till midnight. If the candles kept burning, they were safe. If they burned out, however, it was a bad omen. This tradition came to be called "Lighting the Witches".
10. Mashed potatoes on Halloween
Make up a huge batch of mashed potatoes on Halloween. Place a ring, a penny, a button, a heart-shaped charm, a shell, and a key. Mix everything in so the items are well hidden. Turn out the lights and give everyone a big heaping spoonful on their plate. Ideally, everyone will have an item hidden in their mashed potatoes. According to legend, the one who gets the ring will marry first, the penny signifies wealth, the button - bachelor or spinsterhood, the heart charm - passionate love, the shell - a long journey, and the key is an omen of great success and power. Make sure everyone digs the item out with their forks before chowing down. You don't want anyone choking on a penny!
Every Halloween superstition has a shred of truth to it. ;)