Cue Card: Noob Paladin Tank

I get 'how to' questions from people who start playing a paladin tank on a regular basis. Here are some of the re-occurring points:

Your Buffs

Use Blessing of Sanctuary!
Kings may sound attractive, but Sanctuary is essential for mana returns. As of Patch 3.3, Sanctuary gives 10% Strength and Stamina, 3% less damage taken and 2% mana gained on block, parry and dodge. Compared to Kings, we loose 10% agility for 3% less damage and loads of mana. BoS is superior. If you can have two blessings, get Blessing of Might. If you can have three, get Kings as well.
Note: BoS is available from level 30 onwards. Use Kings before that.

Use Seal of Vengeance!
Seal of Vengeance is the proven superior seal to Righteousness and Command. It puts a stacking DoT up on anything you hit, and grants you 33% weapon damage as bonus as soon as your target has a full stack of 5. Also, when you use Hammer of the Righteous which hits 3 (or 4 with the glyph) targets, each of those gets the DoT.
The Glyph of Seal of Vengeance grants you 10 expertise. Expertise, not expertise rating. It takes you 26 expertise to be soft-capped and reduce a bosses chance to dodge or parry your hits by 5.6% each. 10 Expertise covers a lot of that without using item budget on gear and gives you a great advantage.
Note: SoV is available from level 64 onwards. Use Righteousness before that.

Use Divine Plea!
Divine Plea is used by holy and retribution paladins as a mana potion every minute. For protection paladins, it is used as a damage reduction and continuous mana gain. For that, you have to put two talent points into Guarded by the Light in the protection tree. Guarded by the Light reduces spell damage taken by 6% and refreshes Divine Plea each time you hit something. Add the 1 minute cooldown on divine plea, and you can have it active all the time while fighting. The Glyph of Divine Plea further makes Divine Plea attractive with a flat 3% reduction of all damage taken while Plea is active. So - get the talent, get the glph, use the Divine Plea before you pull.
Note: Divine Plea is learned at level 71. You'll have to wait if you are below that level.

Use Righteous Fury!
This increase the threat generated by your spells by 80%. If something is running off unexpectedly to squash a damage dealer or healer, most likely you forgot to re-activate your Righteous Fury. It should always be active while you are tanking, unless you have an encounter  specific reason why you don't want this bonus threat.
Note: Learned at level 16.

Threat Abilities/Rotation

The best threat a paladin can deliver results from a 9/6/9 rotation. This refers to using your five primary threat moves in an alternating sequence between short and long cooldowns. Short is six seconds, long is eight or nine seconds. Let's look at those abilities:


Hammer of the Righteous
This hits three (with glyph four) targets in front of you. This is extremely handy when picking up groups of mobs. A hit with this ability counts as a direct hit for Seal of Vengeance and will apply the SoV damage over time debuff to the target.
Cooldown: 6 seconds. Learned at level 60. 51 point protection talent.

Shield of the Righteous
Hits only one target, but hits it hard. Boring and straightforward compared to Hammer of the Righteous.
Cooldown: 6 seconds. Learned at level 75.

Holy Shield
Holy shield does two things. It increase your chance to block an attack by 30%, which considering the chance to be missed, to parry, to dodge and the normal chance to block will result in no straight hits anymore. Since we are no longer dealing with crushing blows from bosses, this is less important today, but still a useful damage mitigation factor. It also deals damage to anyone who's attack you block.
Cooldown: 8 seconds. Learned at level 40, 31 point protection talent.

Judgement of Wisdom (or of Light)
This places a debuff on your target. Mana (or health) gain on hitting the target as well as the additional talented debuff from Judgements of the Just, which reduces the target's  melee attack speed by 20%. This is easily missed, but is a significant factor in damage reduction for tanks. All tank classes have an equivalent move, not using it means you are taking more damage than you should. I prefer Judgement of Wisdom for the mana returns, as do most mana-based raiders. Judgement of Light is less useful with the trickle of healing it provides not quite up to countering raid damage effects.
Cooldown 10 seconds. Can be reduced to 8 seconds with 2/2 Improved Judgements talent points. Should be reduced to 9 seconds with 1/2 Improved Judgement. The additional point doesn't provide a gain in threat since there is a short time gap in the 9/6/9 rotation anyway. Learned at level 12.

Consecration

Places the quite visible paladin field on the ground. Any hostile mob in the field will take damage from it. This is useful, but can be problematic if some mobs are not supposed to be hit. It also requires a bit of foresight to avoid damage losses from having put down the field in the wrong place. So choose your tanking position first, pull with that and trigger happy dps and mind and put down the consecration field accordingly.
Cooldown 8 seconds. There is a glyph that makes it last 10 seconds, but this actually creates problems in the 9/6/9 rotation timing and is a bad glyph to use. Learned at level 20.