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Once a station is built or upgraded, it's production lines can work straight away if you manually supply materials. However, for it to really work for you, it needs a Manager and ships assigned to the Manager (see below). The Manger will begin to advertise Buy and Sell orders for wares using a budget that you can define the size of within the Manger's Detail Menu. Those trade deals may be fulfilled by NPC traders, your manual traders or civilian ships that you assign to the Station Manager (recommended to reduce the chance of a ware shortage stopping production). Production Modules will often need multiple types of cargo (Bulk, Container, Energy and/or Liquid) in order to function smoothly, assigned ships offering relevent types.
Station construction
Stations are build by Construction Vessels (CVs), which are sold by XL Ship Dealers and can only build the sorts of stations that are found in the system that the CV is built in. The CV needs an Architect NPC (and also an Engineer for repairs and a Defence Officer for weapons control). Once construction of a station is begun, you can technically cancel construction but it's better to make sure you want to build it in the place to begin with rather than risk the possibility of something bugging out with the CV and/or Architect.
Stations can only be built at pre-defined build locations. Of which there are usually 2-3 per regular zone, or 7 in "empty space" (which you can claim by renaming renaming after a station is built there). The build locations are only visible when you have a CV in your player ship's squad, and building can only be order if there is an Architect already on the CV. If the CV is destroyed at any time after construction begins, you can replace it by being in the same zone as the location and the new CV (in your squad) and talking ot the Architect.
All stations are built from a very similar collection of wares (fewer types than ships):
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