One superstition is that if a pregnant woman walks outside during a lunar eclipse without wearing a pin, she runs the risk of giving birth to an infant with a cleft palate. It's said that we can also tie keys around the waist to reflect the light to avoid problems.
Another common Mexican superstition has to do with the evil eye. We call it "mal de ojo" in Spanish; the evil eye can cause all sorts of distress to people and also to material items. We believe the evil eye can be condensed down to jealousy and desire. If someone looks upon your baby/child with either of these emotions in her eyes, she has just given your child the evil eye. To keep the evil eye away, we tend to ask the person to touch the child at the same time. If a child is suffering from a high fever, crying fits, or nausea we generally think is due to the evil eye. If the person who gave the child the evil eye is around, she must pass a mouthful of saliva to the child to break the spell. If the person that gave the evil eye is not around, an egg is rolled across the child's body while doing an "Ave Maria" prayer. If it is "hard" or "looks like an eye" then the evil eye has caused the child's illness. A red bracelet can also be worn to protect against the evil eye.
I also always been told by my mother that putting Rosemary in my wallet brings me money. I haven't done this in awhile that would explain my lack of money lately : ) My mom also has told me to put Rosemary by the front doors so nobody steals from you and I've been told it keeps the witches away...lol
Superstitions are very old and were told by ancestors. Many people practice these superstitions because they think that they work and some people just don't. Personally I do believe in them; but each person lives their own life and has their own beliefs. Feel free to comment to let me know if you have any superstitions you believe in...