Use words correctly, irregardless of how others use them. Understatement is always the absolute best way to put forth earth-shaking ideas. Puns are for children not groan readers. Go around the barn at high noon to avoid colloquialisms. Even IF a mixed metaphor sings, it should be derailed.
Exaggeration is a billion times worse than understatement.
Proofread carefully to see if you any words out.