Voting looks and feels good, but it does not mean you have done any good. If you want to help others, spend Election Day working and then donate your earnings to a GiveWell.org charity. You’ll do thousands of times more good than any voter.
Your vote matters only if you break a tie. The most optimistic theory in political science estimates that voters in swing states have a 1-in-10 million chance of deciding the presidential election. Everyone else’s chances are far lower.
Casting a vote is thus like donating a Powerball ticket to Australian wildfire relief: 999,999,999 times out of a billion, you’ll achieve nothing.