How to Terraform Mars

There is a huge carbonate silicate cycle that drives the habitability of our entire solar system. We do not have a lot of carbonates on the surface of Mars. This could help us to, if we can somehow have enough CO2, that might help us to warm the climate and things like that. But it's still in the NASA stage and terraforming Mars so that one perspective is not that easy. As of now, our understanding is literally surficial - we just know about maybe one centimeter of the Martian surface.