How do you make loads of gold really fast on World of Warcraft

The quickest way would be to play the auction house. This means buying under-priced mats (materials) for crafting professions, gear, flasks and other items players want/need and selling them for higher prices. This does not always work well though.

Another way to possibly make money is during a holiday event like the Fire Festival where you run around honoring the fire spirits in cities and towns, and desecrating the opposite factions fires. If you are level 80, you will receive approximatly 6 gold for honoring your fires and 13 gold for desecrating the other factions fires.

Other than that, there is not really a way to make tons of gold.