People will usually give generic answers with questions how do I make money.

If everyone does 1 thing the markets become flooded and the profits plummet, so people usually will not give exact things to do.

To really make money as others said look at the market, look at endgame gear see what makes it. Then see if you can farm/gather it. For low levels leather working stuff is a goldmine. Honestly anything that does not drop in Uldah's regions tends to sell decently.