It's very simple, you see:
Affect is an action; this is the anchor that gives you the rest.
From there, you know there is a similar word "effect", and you know effect is a noun, because you know affect is a verb, except for when it isn't.
Now we will discuss how to handle the mirror universe affect/effect pair:
Just to recap, since you know affect is a verb, you know effect is a noun, and now you also know that there is a mirror universe effect that is a verb, and it pairs up with an affect that is a noun.
That affect is pronounced AF-fect, like AFT deck, instead of af-FECT, like, uh, FECKED. The effects are pronounced the same (or so close nobody can really tell), which admittedly does sound rather dangerous in theory, but in practice, you can really only use the mirror-universe effect on purpose anyway.
Make sense? No questions? Great, have a good one.
Other catchy and relatable mnemonics include:
(Note: You may find that, once you have effected the affection in question, there is an undesired effect: an affect that effectively seems to be an ineffectual affectation, in effect effecting unexpected disaffectionateness in spite of your bona fide unaffectedness. Should you be affectioned to this aftereffect, try to avoid becoming disaffected; while you may feel briefly effectless, mitigation will take effect presently and you can be on your way with your effects intact, or something to that effect.)