Start with a purpose
Station archetypes establish a role, while the installed modules determine what the station can actually do. A production rule cannot make goods without a suitable facility.
Assemble the modules
Station layouts connect modules to existing module faces. Plan docking access, storage, power and habitation alongside the production facilities you want.
Supply the operation
Use the module catalogue to see construction materials and build fees. After construction, production and upkeep need a continuing supply of goods. Times and costs are configured reference values and may change during development.