Phase 1: Build a underground base attached to a self-maintained
basic eco-system for oxygen and food. (As much as possible)
Phase 2: Set up equipment for mining in the correct locations.
Automate. Aim is to refine minerals into a giant metal block.
Use CNC machine on those giant blocks, then weld them to create buildings.
Phase 3: Build the space escalator and get power to leave at will.
Phase 4: Spread the word and bring more people & robots in,
this time for terraformation and more cities. Change Mars.