
I believe you make your own luck.
That being said, a good luck charm or two probably couldn't hurt.
Other than filling your pocket with marshmallows from a box of Lucky Charms, what are you doing to improve your luck on Test Day when it comes to the stuff outside your control?
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Judging from the below ad, it looks like Lucky Charms have come a long way since 1964.
The newer ones might help more on Test Day than I initially thought:

Photo by jbcurio / CC BY 2.0
Photo by call-to-adventure / CC BY-NC-ND 2.0