Why should you vote?
I'm not here to tell you for whom to vote. I don't care. Vote for someone. Anyone. Just vote.
I'm not going to tell you things you've already heard a thousand times before (people have died, or are dying, all around the world for the right to vote; since you will probably pay taxes or use services at some point in your life, you have a right to decide how much you should be taxed and how that money should be used). These clearly haven't motivated you to vote before, so why bother repeating them?
I'm not going to threaten you with hypothetical punishments for not voting (not being allowed to complain; being forced to act as Speaker of the House for a week), because these haven't compelled you in the past, and you don't believe any government could actually enforce such unconstitutional laws.
I'm not going to belittle your lack of adulthood by pointing out that not voting is equivalent to being unemployed, living with your parents, getting an allowance even though you do no chores, and letting your mom buy all your clothes and make all your decisions for you. That's not going to motivate you, especially if it does describe your living situation.
I'm not going to explain why democracies are broken (politicians have a vested interest in being reelected; making tough, unpopular, forward-thinking decisions is not going to get anyone reelected). You already know all these reasons, which is why you don't vote: you think that politics don't matter, and that your vote matters even less.
I bet you also think, in addition to it not mattering, that there's no one out there who gets you. No candidate or platform that perfectly encapsulates everything you believe. You probably find it frustrating that there are five or more candidates, and not a single one of them is ideal. You're right and you're not alone.
Even if you were running in the election there still wouldn't be a perfect candidate for you. Why? Well, because if you're anything like everyone else in the world, you might change your mind when it comes time to make a decision or you might make the occasional bad decision. Sometimes you take the easy route (sitting on the sofa), rather than making the tough choices that will be to your long-term benefit (voting).
So rather than waiting for life to hand you what you want on a silver platter, get out there and work towards it. Learn about the candidates and the platforms. If there's a candidate and platform that is more right for you than the rest, then open up dialogue with that candidate and that party. Let them know what compromises you'd like to see when they actually get to the House to try to enact their promises. If there's no candidate that even comes close to representing your interests, run for election, or find someone who wants to run and merely needs your time and money to get off the ground. Above all else, on election day, get out and vote. Get your friends and family and coworkers out. Vote!
And remember, democracy is frustrating, especially when things don't go your way (which is almost always). That doesn't mean you shouldn't participate. You win by being engaged in the process, not by supporting the candidate who wins the riding.
And that is why you should vote.