Earn diablo 3 gold is an easy thing, but if players want to farm it fast, it's not an easy thing, here will tell players the best way to maximize gold find in Diablo 3.
To get pure gold the two biggest factors are how much gold find you have and what act/difficulty you are in(higher is better untill you reach Inferno where Act wont matter). The key facter here is balancing the amount of gold find you have so you can still kill high level monsters. You can also make a pure gold find set (also works for magic find) and after clearing an area for monsters equip your set and go open chests and destroying things that can contain gold/items.
But a better way of getting gold is using the AH, there is no cost to putting diablo 3 items up and there are plenty of people buying items, atm I would recommend focusing on magic and rare level 45-59 weapons with high dps and high damage stats(str/dex/int), but other items with good stats also work.
The reason for the level is that people need to be high enough to have gold, and once you hit 60 it is a lot harder farming for the easy selling items (higher standards). Don't be to greedy, it is better to sell a lot of diablo 3 equipment at a lower price than a few at high, if you can sell 5 weapons at 50k each you will make more than selling 1 at 200k in the same period. Just try and make sure to always use the 10 item slots you can have up on AH.