If and when Democrats take the Senate, they should not confirm any more Trump nominees for anything. And if a Supreme Court justice dies or retires, they should take a page from Mitch McConnell and not let Trump replace him or her until a Democrat is once again in the White House. And just for good measure, Chuck Schumer should read McConnell's words justifying his obstruction of Merrick Garland's nomination right back at him if he objects.
Just vote them down. Like Republicans should have done with Merrick Garland.