Societal collapse is listed by IPCC as one of the likely consequences of climate change. I think we can also see it happening already as a consequence of greed and fear, embodied by neo-collonialism and capitalism. The world as a whole is not in the best of health on a social/societal level. There are many things we can do to help here.
One thing is to act in a Generally helpful manner. Another is to improve ourselves. If we are not in good health, and not acting as a good example, then we cannot expect others to improve their health and behavior either. All of the events leading upto societal collaps can be attributed to unskilful actions, so it is important to avoid those.
Once we are on the path to improve ourselves and help others, then we can also invite others to join us in the positive changes we would like to see in the world. This can be done in many ways, I'll mention some in order of extremity.
What if everybody, with all their actions, would stop to ask: “What would happen to the world if all others did the same as what I'm about to do?”, I'm sure the world would become a better place for it. If you want others do do something, then do it yourself first, and publicly if appropriate. If you want others to not do something, stop doing it yourself and publish it.
Sometimes, protesting loudly from the comfort of your home, can create a change of mind in others. It's not the most powerful way, but since it's so easy, I think it's worth to use this tactic. It works much better if you're a living example, and not just sprinkling blame around… obviously.
Another way to discourage is to create negative feedback on the behavior. If your tennant doesn't close the doors, make sure the heating or airconditioning system has a low power, so that the open door has more uncomfortable consequences.
Hanan Cohen is an activist that fights against the fascist government that is committing atrocities in Gaza at the time of this writing. He wrote this brilliant quote, so I'm a fan now:
we forget that what a person says is not who the person is. The mapping between what's in our heads and what comes out of our mouth (or fingers!) is imperfect. It takes a while to get it right. And some things can't be expressed at all without totally missing the point
He also makes a very solid case as to how and why we should do activism, Does right, and sets the example. I'm not an authority on this topic, but I think that if other means fail, activism is very important to keep society functional.
If all the above things don't work, some might recommend violence/force. I don't. To endure something bad is one kind of suffering, to behave badly is more suffering. Some things you can walk away from, sometimes the suffering is inescapable. Even when there are no other options, violence rarely solves problems in my opinion.