Speaking from a level 70 point of view I can only tell you how to do old way because the new patch hasn't been out long enought to work a char from 0 to 70 yet. But here was how I made 70 in a reasonable amount of time.
1. Quest, turn in then group and do some instances then quest some more.
2. While questing keep on killing the quest animals after you have done the quest untill you see the amount of exp drop then turn in the quest then do some more dungeons. As these for the time invested in them level you up faster then questing. They also give you alot better gear so when you go back to questing you can survive a lot longer before returning to a town.
3. Get the biggest bags you can aford and fill all bag slots and pick up everything and haul it back you will make twice as much cash as those who only pick up the greens and the quest items.
- Be patient, and resourceful. Just try to enjoy the game.
- When you have rested XP, grind. When you don't, do quests.
- When grinding, always buff up (food, elixirs, weightstone, sharpening stone. Anything!)
- When questing, get other questers to join you on general chat.
- Study your quests and do them in batches, or chain them together.
- Use google to find good wow grinding spots. Lots of FREE lists out there!
- Do instances/class-quests to get cool gear, you'll be much deadlier and level faster.
- Use The ARMORY to see how you can improve your gear frequently. Make a list!
And always remember, there are no shortcuts. Levelling to 70 takes long. Those nabtards like Kopp and that other skank claim "8 days" etc but remember those are 8 DAYS PLAYTIME, which is still say 200 HOURS roughly which boils down to 3 MONTHS if you play a couple of hours per day. Don't be fooled by the numbers!
All you idiot nabtard guide/gold seling cornholios out there, and the ones promoting you, you guys SUCK! For shame!