Supporting a 3rd party would be a solution. A terrible solution that has historically proven to only hurt the cause you are trying to support. But bad solutions are at least still solutions.
Changing the election system is another solution. The National Popular Vote Interstate Compact is one of the many issues I consider when weighing who I vote for. But the reality is that law has not passed and may never pass, so we are stuck with the electoral college and first-past-the-post voting system in the US for the 2024 election.
Then there's coups. If you're advocating for political violence I suggest you visit a nation experiencing it. There's a reason so much of the country was terrified watching the news on January 6th 2021.
Then there's leaving the country, which is basically just an option for the wealthy or otherwise lucky exceptions. Not really fixing the system as much as abandoning it.