There are different ways to participate in creating a solarpunk society, like working to plan, develop, or live in communities that are mostly powered by solar energy, incorporate adequate greenspaces to bolster residents' mental health, fundraising for community gardens, etc.

Here's a neat article that was posted to the mander instance on an area in California where one mostly-solar community has already been built, and two more are in development: https://hardware.slashdot.org/story/23/06/18/206226/californias-first-solar-powered-microgrid-neighborhood-has-a-giant-community-battery