Writing to your local and federal Government. It won't help but at least it'll show them that people are watching them.

Attend every protest march you can, organize protests yourself even.

If you see anyone being harassed, don't ignore it and think someone else will step in. Step in yourself.

This is a good guide: https://www.google.com.au/amp/s/www.themarysue.com/bystanders-harassment-guide/amp/

It works for any type of harassment.