The movie that affected Ann
had no effect on Ed.
If you can remember that sentence, you can solve about 90% of the affect-effect confusions you face in business writing.
In that sentence, "Ann" begins with "a" as does "affected," which is a verb.
"Ed" begins with "e" as does "effect," which is a noun.
This mnemonic rule is reversed only in relatively rare uses of the words. For example, if you deal in psychology, you use the noun "affect" to mean visible emotion: "He showed little affect."
In rather stilted English, a person could write, "The judge ordered the company to economize, so the company effected many cost-saving measures." This rather rare verb "effected" means "carried out" or "implemented."