How do I play Warrior?

[Teleniel]

Defiance is your bread and butter "Tank" stance. If you expect you're getting hit, it's generally safe to say Defiance is the right stance.
Deliverance is your "DPS" stance. You can learn to stance-dance into this while tanking but there are things to be aware of

• Your Max HP is 25% lower
• Your Healing Received rate is 25% lower
• You generate less enmity

Your primarily rotations fall into 3 groups

• Threat Generation: Heavy Swing > Skull Sunder > Butchers Block ... BB-Combo
• Damage Mitigation: Heavy Swing > Maim > Storm's Path ... Path-Combo
• Increased DPS: Heavy Swing > Maim > Storm's Eye ... Eye-Combo

Opening threat rotation and threat management are key to being able to stance-dance. When you are MTing you will want a good opening rotation (this is what I use, might not be BEST but it works for me)
Defiance > Infuriate (before pull) > Heavy Swing > Unleashed > Skull Sunder > Berserk > Butchers Block > BB-Combo > Deliverance > Heavy > Maim > Fell Cleave > Fracture (at this point you will be pacified)

After that you're probably going to have solid hate for a good 2 minutes before needing to worry about someone creeping up behind you.
Path-Combo / Eye-Combo will help reduce damage you take and increase damage you deal
Fell-Cleave is your best single target ability you can usually use it as soon as you get stacks build up
Decimate is your best AoE attack, if you have stacks use them! overpower is great but will eat your TP like no tomorrow.

If you know there is high incoming damage you will need to decide how many cooldowns to use. Outside of maintaining threat, consider Defiance to be a cooldown that can be used as needed (at a DPS loss). Many fights once you learn the mechanics don't require the use of Defiance often.

Hope this helps get you started!