First, you need to reach level 60. That's easy, since the market is overflooded with cheap, high damage weapons. Get one of those and replace it every 7-10 levels or so. If you can, a socket can really kick up your early damage with a ruby. You should dual weild. You should also socket a helm with such to boost your experience. Every piece of gear you wear should include dexterity, vitality and attack speed. Anything else can be nice, but superfluous.

Skills and runes you choose hardly matter at this point, but I suggest a mix of the following. Don't get two mantras, and don't get two generators.

Fist of Thunder
Crippling Wave
Sweeping Wind
Breath of Heaven
Mantra of Conviction
Mantra of Healing

As for passives, resolve, seize the initiative, guardian's path and transcendence are all good choices.

Once you hit 60, Inferno opens up.

Whip out one of the following items:

...and pick one resistance at random. Say, arcane.

Now, you'll sift through the auction house looking for items with: All resistances, arcane resistance, attack speed, dexterity, vitality, and many sockets.

Good values will look like this, kinda:

15-20% attack speed
~50 arcane resistance
~60 all resistances
~100+++ vitality
~100+++ dexterity
1-3 sockets depending on the slot

Once you have every slot of gear with at least 3-4 of each stats, around such values, you're ready to use a new skillset! No, not really. Just go for runes that are more defense oriented, like concussion for crippling wave and so on.

Make sure you use the One With Everything passive. Your arcane resistance will turn into all resistance, giving you a big survivability boost. Oh, and Time of Need on Mantra of Healing is pretty kickass as well, improving that amount by another 20%.