There are several ways to make fast gold on WoW, but which way you choose depends on your skills and preferences. You could decide to focus on a profession or two to help you earn that gold, or you could decide to devote your time to the auction house. You could also choose to spend your time doing daily quests to build up your money or do lower level quests when you are at level 70 in order to be rewarded with gold.
If you have reached level 70 and still have not been able to acquire all the items that you really, really want, you're in luck. In order to make fast gold on WoW at this level, all you have to do is log in each day and perform the daily quests. These are a series of quests that reward you with an average of 10 gold per quest. Although you are limited to doing 25 of these quests per day, you can still earn a substantial amount of gold in one day by completing these. An average of 10 gold per quest for 25 quests adds up to quite a bit of money for one day's work.
If you have not reached level 70 yet, then you might want to consider saving some of your lower level quests until you do reach it. By doing these quests at level 70, you will be approaching gold rather than experience upon completion, which can add up fast if you've saved enough quests for this stage. This is another way for you to make fast gold on WoW once you reach level 70.
If you have a knock for trade and economics, spending time at the auction house will be a worthy experience for you. While you are there, you can pick up on which items are more likely to sell and for how much by comparing sales. You'll also be able to figure out when the best times are to sell certain items for more money, and determine which items can be bought at cheap prices and then sold at higher rates. You will also get a feel for the market values of items compared with the claimed values that the auction house provides. If this is an area of expertise for you, then hanging around at the auction house will definitely enable you to make fast gold on WoW.
If you would rather be free to wander around instead of staying in one type of place, then you might want to choose a gathering profession. Being a gatherer is a quick and easy way to make fast gold on WoW. By focusing on mining, skinning, or herbalism, you can make reasonable amounts of money while being able to explore the world. The items you collect as a gatherer are usually in high demand and sell easily at the auction house. Your only limit will be the amount of items you can carry at one time, but you could invest in larger bags that allow you to carry more instead of running back and forth to the auction house to sell your items.
These are only some of the methods you can use to make fast gold on WoW. There are plenty of other ways to become wealthy in the game. If you play enough, you might even discover some new ways yourself. No matter which method you choose, you'll be on your way toward eating that coveted gold.