In some states, like California, you can point right with your right hand to signal a right turn. Pretend you're invisible. Act as if car drivers can't see you. This is a variant on the general theme of riding defensively. Pretend they're out to get you.
Some drivers are total nutcases.
Don't bait them. Just get out of their way. Write down their license numbers and report them to the local police. Live to ride another day. Share the road.