One of the harder decisions you'll every have to make in the English language is whether to use the word affect, with an 'a', or effect, with an 'e'. And one of the reasons it's so difficult is because the words sound and look so much alike, and also their meanings are intertwined. The best way to remember the difference is to know that affect, with an 'a', is a verb, and effect, with an 'e', is a noun. So when you have a sentence and you know need one of these words it's important to find out if you're looking for the noun or the verb.
So we might say, 'The legislation effected my income.' Say there's some tax legislation, it's passed, and it effects your income. We use the word affect, with an 'a', because the legislation is the actor and affect is it's action. We need a verb here.
But if we say something slightly different, like, 'The effect was I had less money but more services.' We need 'effect' with an 'e', because here we're talking about a concrete thing, a noun. The effect, or result of this action was that I had less money, but my city had more services. So I hope that this helps you understand the difference between affect and effect. Just remember that if you're using the 'a' word, you're looking for a verb, and if you're using the 'e' word, you're looking for a noun. I hope that clears up the difference.