Mnemonic devices help you to retrieve what you have learned and to hold arbitrary information in memory.
Mnemonic devices may work quite well in some areas of study, but I do not recommend mnemonic devices for mathematics because:
• What you are trying to remember is not arbitrary.
• The mnemonic device obscures the math concept.
• The mnemonic device obscures connections and context.
• The mnemonic is harder to remember than the math.