Regular, every day rockets are used to blast material and parts and stuff from different countries into space to assemble a space platform in very low Earth orbit (much lower than the ISS). Because it is in such a low orbit, it will lose altitude very quickly. That's where VASIMR thrusters come in. They should already be equipped on the ISS by the time this project begins. VASIMR thrusters will reduce the need to keep blasting fuel into space so the platform can stay in orbit. As long as the platform is close enough to the Earth, it should be able to siphon hydrogen atoms off of the upper layer of the Earth's atmosphere and use it in the VASIMR thrusters.