Greens from the AH before 15ish, and I also supplement using the AH on top of the following at every 5-10 levels (definitely at 58-60, 68-70, and 80). Once he hits 15ish and can do instances, I'll do at least a few at the proper level (maybe slightly over-level for the place) so I can get the random reward bags, plus some good gear (hopefully) from the instance itself. 58+ I do BGs to get all the good to great PVP gear, and usually they are upgrades for the crap I have at the time. 68+ quest bot to get some real solid rewards, switching off between that and instances. If I still have any real crap gear at this point, I make a trip to the AH. Once I hit 80, buy stuff with the Triumph emblems I have from running normals, to gear up for heroics (depending on class), and round it out with either crafted or BOE epics on the AH. If you are poor at 80, just run BGs until you have a full set. If you are only going to ever do herb/mining, go the BG route all the way. Cheapest and easiest, IMHO.