Call the President. PHONE NUMBERS:
Don't stoop to Trumpian levels. IOW - Be an adult. Speak calmly about one specific position with which you disagree and why. Write it out before you call. State the names of your senators and representative. Tell Republican Trump what action/s you will take to either support or work to defeat your state's congressional representatives' re-election based on their position on this issue. Say thank you, and hang up.
Repeat as necessary.