This page is mostly to be used in tandem with the Youtube video guide that can be found here,
http://www.youtube.com/watch?v=zb_E3BMGQ8M

What is not in the video WILL be covered here, but only briefly as I don't like to sit around and type for days.

This is what works for me and my team when we need me on tank and I choose Shen :P so if you have suggestions on what might be more efficient, feel free to comment. Or troll me.

The most recent patch when this guide was made was the Xerath patch.

These are my standard tanking runes, they give me as much tankiness as possible early while holding up on the MR/L since I usually don't itemize for MR as much as health/armor on Shen. Same goes for the masteries, 0/21/9 sounds pretty standard to me for tanks and not much else to be said there.

Maxing vorpal blade before taunt or shield may seem strange but his Q is fantastic for farming or harassing in lane as it has a low CD, and relatively high damage. This, I consider more important than taunt at lower levels since I like to (actually I only) put myself solo top with him and farm like a phyco to become an immovable object by mid game when the team fights start.

I take Teleport and flash as my SS. Flash should be expected (as you should run it regardless of who you are) and Teleport allows me to return to my lane immediatly after using my ult in order to save or assist someone in another lane in order to not miss out on that precious farm. It also (later in the game) allows me what I call a sub-ultimate.

Ward coverage is important so your team mates will usually have a ward or two on them and if not somewhere near by already placed. when in trouble I have wards to Teleport to so I can assist my team faster than running. Of course I'd use my ult if it were up, but you'll find quickly that you need to be flying all over the map constantly, and everyone likes to think they are your 'shielding priority'.

Ideal Build+Build order. (buying health pots and wards as necessary)

Ruby Crystal
Heart of Gold
Boots of speed
Giants Belt (Into Warmogs ASAP)
Mercury Treads
Wardens Mail
Force of Nature
Phage (Into Frozen Mallet ASAP) (Sidenote: If your team is more DPS than AP DMG consider Rylais Crystal Sceptor instead of Frozen Mallet as your abilities scale strong with AP)
Combine for Randuins Omen
Giants Belt (Into Sunfire Cape)

Now That's in a perfect world, But keep in mind that you need to be countering the enemy team as much as possible as the tank.

If you look at my suggested build you'll notice something very quickly.

It's freaking expencive.

So you'll need a solo lane (preferably top, usually more manageable over mid) to farm like crazy. You'll also need to involve your self in as many fights as possible and get your jungler to gank your lane as often as possible.

For the most part, The tanky DPS champs get top solo which works, but if your teams play style is just shy of -get in the face of the enemy and push them back, and back, and back, all the way to the nexus- then giving your tank the solo lane to farm is probably for the best. With farm it's much easier to stack defences than it is to stack damage, so with the solo lane being occupied with a tank, come mid game, they'll be able to take MORE than enough pain for your team to steam roll through a tower or two.

I find that the above strategy only works with tanks like, Shen, Rammus, Malphite, and if your good (which I am not) with Alistar he works too. These guys are good since they GET tanky REALLY fast. Rammus and Malph have things that scale with armor, Alistar just needs to hit 6, and Shen doesn't miss creep kills (not a single one between your basic attack and vorpal blade) so the gold generation is really High.

Well that took a lot longer than I expected but I suppose the more comprehensive the better right?

TLDR so you skip to comments to see if worth reading? Reading at all not your thing? Well here's the Youtube link to the Video version of this guide :D

http://www.youtube.com/watch?v=zb_E3BMGQ8M