How do you write a persuasive writing task?

DON'T FENCE SIT! Fence sitting is where you say "I think that we should have (blah blah blah) because it (yada yada).... but then again we also shouldn't have it because (and so on)" You want to prove your point and make it stick. Even if you don't believe in your topic, make the other person believe in it. If you sorta want one thing, but also want the other, pick one and go with it. Fence sitting will only make you sound like you don't care about what you are writing about.

Never say "I think". We know that you think that, because that's why you are writing it! Make your points solid. Don't ask questions, answer them before they are asked.