Assuming you're in the US apropos of the proximal elections.

Several times it turns out.

1. Because y'all for some reason elect sheriffs, vote for the sheriff who won't steal your ballot boxes.
2. Vote for whatever aldermen/councillors/bureaucrats that run your village/town/area that won't just appoint a bunch of partisans to (mis)count the votes, should the ballot box still exist or use the "hanging chads" technique
3. Vote for your senators
4. Vote for your representative/Congress people
5. Vote in party primaries
6. Vote for electoral college people

Apologies for the terrible errors above, I don't know that much about how it all works and all 51 states.

Depends. How many charges do you feel like facing in court?

Every time.
Vote early; vote often.

Haha look at this guy, he thinks his vote counts

(It's a poll, at best)

I vote every election, and you should too! It's funny

An odd number of times, otherwise the arrow greys out again.

If you are a billionaire? Once. And it doesn't matter which team wins, your policy preferences will still control what happens next.

If you aren't? It doesn't matter your vote simply doesn't count for anything except which puppet of the ruling class you'll be seeing on TV for the next four years.

https://act.represent.us/sign/usa-oligarchy-research-explained

That's not hyperbole, that's the actual answer.

Are you the guy writing in Mickey mouse every election?

Depends on who you are voting for