Let's strap a couple rockets to it and move it to lunar orbit. Empty it out of personnel, let it do a nice, slow burn to lunar orbit. Slower is cheaper in space. Let it take however long it does to get there, and then we can start sending unmanned Dragon capsules back out to resupply it and lunar shuttles via SpaceX. This would be a good "next step" toward eventually building a permanent structure on the lunar service, and could eventually serve as a sort of waystation for missions on the way out to Mars.
Why would this be a good "next step"? Any permanent structure on the Moon or in lunar orbit will be unmanned (due the exorbitant expense of keeping humans that far out) - what would be the point of a structure whose only purpose is to be a habitation?
If (hopefully) we find a way to harness fusion energy to make an efficient rocket engine, the components on earth are better for fusion than the components on the moon (He3 is not a particularly good fusion fuel) - why wouldn't we just ship the components from the earths surface and fire the engine once to go to Mars?