Might be easier to terraform Venus, a planet much more nearly the size and gravitational pull of earth. First problem is getting the excess heat radiated off, until the very hot atmosphere cools enough to allow the settling out of the volatile sulfur compounds (as sulfates), and the release of enough water to to act as a medium for heat moderation to still lower levels, within a habitable range for earth creatures. Seeding the Venusian atmosphere with “dirty snowball” comet material from meteors, organized in a vast engineering project, would vastly speed the process.