Here are some that I don't think others have mentioned but that are big ones in my own interpretation of solarpunk:

• Repair things. Clothes are mostly what I have the skills to repair myself, but repairing things that are still useful like a phone or laptop that still meets your needs
• support open source and free license software. I think this one is more a part of my own interpretation, but to me open source/FLOSS software is like the software equivalent of employee owned, or community owned and operated. And that's super cool! It sidesteps a lot of the problems of profit motives ruining everything good, because some amount of the motive in the FLOSS world was an ideological idea of good to start with. With the whole fedora controversy about paywalling source code, that's not even as shitty as the corporate world is by default and the open source community generally STILL wouldn't stand for it.
• Support your local economy! Farmer's markets are a great way to do this, but I always try to look around for local shops when I need something like stationery, or local restaurants if I'm eating out. Searching google maps for a category of business (like "stationery") and then looking for the non chain options is a helpful way to find places, but its also just a nice reason to pay attention to your surroundings when you're out and about!

Edit: massively agree with voting!