In the US? The IRA is a very good model. Hard to overstate what a good piece of legislation it is. Doesn't go far enough, but it makes some serious strides.

Promote electrification. Renewable energy generation is already cheaper than fossil fuel, so with minimal additional incentives the market is going to wipe out grid fossil energy production over time. Calibrate your incentives and penalties to make it happen as fast as possible -- we aren't there yet, but we've taken major strides.

You'll need to do a LOT of grid enhancement in the process. As more electrification occurs, you'll need better transmission of that electricity. A lot of the utilities have vastly miscalibrated incentive structures right now, which favor building major capital projects over doing repair and maintenance. Better regulation can fix this, though some of them are so incompetent and corrupt that they long-term probably just need to be nationalized (looking at you Central Maine Power/Versant). Re-conductoring is a good place to start for this because it's cheap and can increase current grid capacity by something like 2-3x. Large grids with a good mix of wind/solar and dynamic pricing should be largely resistant to any intermittency issues of renewables, by some energy storage sugar on top will take care of that.

Side note: the main thing pumping the breaks on more renewable energy generation facilities is not actually a lack of demand, it's interconnection queues.

Another prong is urbanization. You massively reduce emissions by reducing vehicle miles traveled (VMT). Good urbanism reduces VMT, creates more financially sustainable towns, and also more pleasant, safe, and healthy environments for the average person to live in. Strong Towns has a lot to say about how you can start pushing for better urbanism right now. There's little more you can do for total emissions as an individual than helping your city avoid expensive and dehumanizing sprawl; show up to your MPC/city council meetings and advocate for good urban policy.

We can further cut back on emissions by reducing the reliance on interstate trucking for freight. Trains can (and should) be electrically-powered and are FAR cheaper for a society. Delivery "last miles" can be done by various EVs pretty easily. For the US, this pretty much requires nationalization of the right of way/track (and then, ideally, deregulation of the freight operators). That is, make the train network function a lot more like the current highway network. Bonus points: ~80% of microplastics in our water are just tire dust. Let's do less of that.

Industrial heat is another major pillar. Places like steel and concrete plants need to switch to heat batteries powered by electricity instead of fossil fuels. This tech is ancient and reliable, but still not at scale, but at least some promising pilots are already happening. And the minute any of them work at all, they'll take over fast. Because renewables + heat batteries ought to be a lot cheaper and more reliable than furnaces + fossil fuels once operating at scale. And the facilities will also be able to make use of aforementioned renewable intermittency to save even more money (e.g., charging their heat battles at nadir hours where energy prices go to near 0 or even negative).

We'll also need to do some stuff that is politically sketchier. Reducing certain kinds of consumption (industrial beef, fast fashion, tariff-loophole import goods, etc). But those are higher-hanging fruit and it's ok to procrastinate on them a bit if they're too politically difficult right now.

Well the first step is to reduce or at least drastically eliminate the amount of CO2 that is being released in the first place. Removal of carbon from the air is necessarily going to have to be a down the road plan. It literally cannot happen to any scale if we are still relying on fossil fuels in the first place.