• Vote for political parties with strong climate policies (such as rapidly reducing fossil fuel usage; banning new coal power plants; banning new coal mines, that kind of thing.)
• Write letters to currently elected representatives letting them know your priorities. (Those priorities, in the context of climate change, should be related to reducing fossil fuel power generation; and increasing the usability / reliability / affordability of public transport and other non-car based transport.)
• Lead by example in your actions. You are probably not the problem anyway, and your own climate impact is close to nothing compared to some companies and some rich individuals. But you can still emphasize that cutting emissions is important and achievable by adjusting your lifestyle. Buy less throw-away stuff. i.e. use things for longer, or use less things - don't produce as much waste. Reduce your car usage, by commuting via bike or public transport. (In some places this is very difficult; but it only gets easier when there is pressure to improve it. Help create that pressure.) Reduce energy waste from heating and air-conditioning by putting conscious effort into when you open & close windows and blinds to control temperature; and by putting more focus on your own temperature rather than the temperature of a whole house.

... Ok. I could go on. But I'm just saying ideas off the top of my head, and you've probably heard it before.

All this stuff is a bit like the health benefits of exercise. Everyone knows that exercise will improve pretty much everything about them. They'll sleep better, be more productive, more alert, think clearer, their mood will be improved, they'll be stronger, they'll live longer, etc. ... But yet people often still neglect good exercise and instead ask around for easier health tips. I think the climate change situation is a bit like that. Everyone knows what to do; but many people just kind of stall and have little excuses or justifications about why they won't do those things. So not much happens.

My biggest suggestion is this: don't try to be a hero. But just make sure you aren't the problem. Be better than the people around you. That's enough.