In the World of Warcraft, mining has become one of the major and the most profitable gathering professions since the release of the Burning Crusade expansion pack. Mining is a great way to WOW power level up your character.
To start Mining
To start out with mining there's obviously going to be a difference in the beginning for Alliance and Horde because each faction starts in different areas until after a certain level when they freely roam through the same zones. I could explain the preferred routes to you but I think by drawing them you will have a better understanding. Don't forget to go back to the trainer at the appropriate times so that you can advance your skill to each new maximum.
Gathering the metal from the nodes
The first is simply by gathering the metal from the nodes that you find. If you are still WOW power leveling your character, simply mine as you quest. This is the least painful method. You will find more than enough nodes to level yourself without even noticing the effort. If you are already level 80 and want to wow powerlevel Mining, you should find zones that have a lot of the highest type of node that you can mine and plan a circuit around it.
Take advantage of skill ups you get by smelting
This method requires you to have some gold to throw around already. If you don't have a lot to spend, you can use this method to get through low level mining faster and then switch to the gather method outlined above. Purchase ore from the AH and smelt it until the recipe turns grey. There will be gaps where you will need to gather and you will need to smelt the rare metals like silver, gold but this method can save you a lot of time.
Since smelting was buffed, the need to mine ore has largely been eliminated. If you have the world of warcraft gold, you can just buy ore from the auction house, smelt it and sell the bars. Then you move on to the next recipe. You will neither make nor lose much wow gold this way but you will WOW power level mining as quickly as possible.