Bishops are not Christ. There are plenty of other Catholic and Christian charities you can give to that will do actual good work in your community than giving a check to your church that's going to be turned over to some money-grubbing bishop so he can fly to Rome every year and use Grindr while he's there.
You can offer to pay your parish's electrical or water bill directly so that you don't have to turn over a check or cash to some unaccountable Bishop who does not care what the diocese's laity have to say about anything. You can write a check or give cash directly to St. Vincent de Paul or do what I do when I have spare cash: put it in the poor box rather than letting it be collected during the mass.
You cut off the money that the Bishops are getting, that puts pressure on them to do what you want them to do. Then you release a press statement about what is it that they're doing and why you oppose it. Again, Catholic Answers podcast had a whole episode on how the laity can hold liberal and corrupt bishops accountable and they had some great ideas.