Trading is initially quite difficult, however gets far easier as you progress the story and get some assistance. If you take a look at the sector information of the Captain's PC it also indicates the main imports / exports from each sector. If you follow this advice and travel Orion --> Beehive --> Pleiades you will have far more success with trading.But I have to be honest I'm struggling with getting the money started in this game.
There is also a map / hint system that will make it easy to progress the main story if you are not aware of it already.