Love all these idea, keep 'em coming. I'm going to take this down a different branch -- what can you do as a person who cares?
Join the International Dark Sky Association. Members are taught how to make a difference in their own community, town, state, country and the all over the world, whatever you have the bandpass/time/energy for.
Use your digital voice.
Sign petitions like this one about overly-bright car headlights.
Like, comment on and share Youtube videos about light pollution. This allows producers and news agencies to see this is a groundswell of many voices all wanting the same thing.
Why You Should Care about Light Pollution
NEWSY.com In Real Life: Dark Skies
Why We Need Darkness | Paul Bogard | TEDxBratislava
Plan a schedule in your week to read an article about light pollution appearing in an online publication and bring it up in a conversation or share it with someone.
With Good Lighting and Justice for All
Goodbye, darkness: Light pollution has increased 49% over past 25 years, study finds
If it's a newspaper article, consider writing a letter to the editor about it. (This must be done in the days following the article, when it is still "news.")
Buy light pollution books (and review them online), give them as gifts.
Ex. The children's book: Bright Sky, Starry City by Uma Krishnaswami
Support people doing the heavy lifting. Follow them on social media. Bring them up to others when appropriate. Share and spread their words/actions/plans.
Alejandro Sánchez de Miguel
Thanks Cloudy Nights people!