Effect v. Affect

(1)

Let's start  with a rule of thumb: Affect is a verb; effect is a noun.

That movie really affected me (moved me emotionally).
Your policies will not affect the realities of the immigration crisis (influence).

His words had a great effect (impact) on my soul.
The effect of your policies has been to destroy all faith in government (result, impact).

(2)

Now, sadly, we must break that rule. But before we do, make sure it is clear in your mind.

Effect is also a verb.

Damn. But its meaning is quite specific and its use is less common than affect. It means "to bring about"  or "to cause to be" or "to carry out". Also, it will often be found in the company of the word "change", or "transformation", "escape", "feat" or "exit" - it contains the idea of doing something difficult (He effected a handbrake turn at 90 mph while clutching a cigarette with one hand and making rude gestures at the police with another) .

To effect real change, we need to take radical action (to bring about, make happen).

She effected her escape by digging a tunnel with her teeth (made happen, succeeded, caused, managed).

(3)

You might now feel I am deliberately mocking you, but in some very limited cases affect is a noun. It is more or less limited to the world of psychology, where it means "observed emotional response".

The dull, despairing spaced-out affect is symptomatic of student vocabulary anxiety.  

But you need not really worry about this last one.

If confused, go back to the rule of thumb (1) above. It will stand you in good stead for many a year.