I doubt there are many climate scientists on here, and I am certainly not one, but the problem as I see it is that the public and industry generally are resistant to subtractive solutions: driving less, going on fewer flights, carbon taxes and so on. Therefore the best solutions are additive: planting billions of trees and investing in industries that reduce carbon emission. Planting trees in particular is something that is- a) simple b) fairly cheap c) has a range of other benefits such as helping to improve air quality and reduce water runoff, preventing floods. d) helps wildlife more generally

I know it's more complicated than that, but that's a good place to start. Perhaps even pay people to grow trees on disused land.