A friend of mine used to make 100s of mils a day with trade runs, its useful for new players but I wouldn’t suggest its the best way to make ISK, I haven’t done any recently myself and if anyone can send me some traderuns, i’ll expand this part of the tutorial. For now I can explain the basics:
You need an indy or another ship with descent cargo capacity, find a place where something is sold cheap, then try sell it at a higher price somewhere else, it requires a lot of planning and research and is therefore very time-intensive to start with. But of course there is the autopilot once thats all done.
“exploits”: This used to be a famous one, put up a large sell order for a “low” price, and a buy order (with an alt) somewhere else (a bit far out) once someone bought the stuff cancel the buy order and the money is all yours… This is harder now days though , and finding an item suited for this is difficult on its own.