evridired - While it may seem obvious, questing is going to be the main way most players choose to level, especially if you're playing solo. You'll find various quest hubs while you're out in the new Outland zones, so you should work your way through these to rack up that experience.

You'll also see more of the story this way, so unless you're racing to get to level 70, questing can help round out the world you're in.

lojato - What level are you at? you probably know the only way is quests.
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