Take a look at what sells. Right, ? items for quests are good sellers. People will pay well for that last stupid spotted butterfly, etc.
Find an area of green ^^ mobs. Turn off exp gain. Yeah, it hurts, but turn it off. Farm them until you can't stand it any more. Go sell the adepts and crafting books you gain. Most other stuff u get just sell to merchants.
Always go out w/ a wholesaler task. Fill it before coming back.
If you are hunting gnolls collect the paws, eyes, ears etc. (lore items) - same for orcs and any beast that has a "mastery quest" - you can sell these items to players wanting to finish these quests.
Basically while filling up your packs w/ stuff to sell to players, you should be occasionaly bopping to the merch to sell the other drops - the saliva, the so-so pieces of armor, the adepts for which there is no market becuase they drop so much (spirit of badger), etc. = to keep room in inv for the stuff to take back. When it's time to quit, set up in your room at your market board and make money while u sleep.
Warning, the market for harvested items is soon to vanish - well, soon to take a major hit. You used to be able to finish the wholesaler quest by buying these from the broker. This is marked for nerfage and may already be gone as of this morning. That is why you could sell iron clusters for 60 c - the player buying paid 72 c and made 8 c profit on the quest reward. But that's soon to be nerfed - if not already.
In fact, if this was pumping as much $ into the economy as I think it was, prices over all may come down. Hold off buying that pricey adept if you want - and see if prices don't come down over the next few weeks. When people can't count on easily clicking a few gold here and there... they won't spend so freely. Copper clusters priced ridiculously at 9g will come down to a more sensible 3g, for example.