Vote as left as can make a difference in every election. Sometimes this will mean voting for someone who's identical to the Republican on 99% of issues because they're the only other candidate who can win.

Protest when the opportunity presents itself. This won't stop them, but it will show some people that they're not alone in being pissed and freaked out by all this.

If given the opportunity, make life suck for anyone who voluntarily associates with the admin. Sometimes that means taking a moment to share some unsolicited citizen feedback at their job or when you see them at random businesses, and sometimes it means taking their money for a coffee order and then dropping the ticket on the floor. Just make someone's day a little worse, and make sure they know it's not just because you don't like them, but also their choices and beliefs.

Help people around you who might be negatively impacted. The nature of the help is something you'll have to figure out in the moment.

If the situation becomes dire enough, remember why the second amendment exists and exercise your rights. Or flee to Canada, which is a valid option. People are worth dying for, a country isn't. And anything worth dying for is certainly worth living for.

Unfortunately, because they won the election and got the congressional votes too, there's very little that can be done inside the confines of the law. Right now they are operating inside the broad outline of the law, so it's harder to justify extrajudicial response. When that changes, that changes.