1. Mine Cave: Clear up your inventory and buy a Twin City Portal from the NPC named Pharmacist. Enter the Mine Cave tot he north west. When your inventory is filled with ore, right click on the Twin City Portal to return to the Twin City, then sell the ore for a profit.

2. Lure to the Guards: If you have no money left, you can lure enemies near guards who will strike them down and usually drop money. Guards get well paid, so they don't need the money - you can pick it up.

3. Team Up: Teaming up with others is a good way to level-up and get rich. Higher level players won't care about the gold drops from the monsters, they just want to gain experience from power-leveling you. So you can pick up as much as you want from the monster drops.