Although I still think that Mining is the number one profession in WoW when in comes to making gold, Enchanting is a close second. Skinning and Herbalism do make a lot of gold as well but they don’t match the potential of Enchanting.
We all know that selling enchanting materials in the Auction House is free. Plus there is a never ending demand for enchanting materials. There are lots of ways to profit from Enchanting.
One way to profit from it is to buy cheap greens from the Auction House and Disenchant them. Then the mats you get from the Disenchantment could be sold in the Auction House.
Another way is to find someone that can make a Fel Iron Blood Ring or Golden Draenite Ring. These are the cheapest items to make but would be rewarding if disenchanted. According to my server’s economics, each ring would cost a maximum of 3 gold to make. When disenchanted, a ring can give you 2 arcane dusts or 2 lesser planar essence each. Plus there is a chance that you could get small prismatic shard from them.