Hello and welcome to my guide on tanking.
This guide is intended for moderate players who have a feel for the game but are newer to the tanking role.

This guide includes some helpful tips for beginning tanks to avoid common mistakes that I've seen time and time again.

I tend to ramble about things like this so if you need clarification, have comments or suggestions, or just general statements about my guide. This is my first guide so please be patient with me and I hope to fix any issues as soon as i find them. Thank you for choosing my guide and I hope you enjoy reading.

As you've seen during your League of Legends experience some champions are more prone to having higher health and are capable of drawing fire for squishier allies. These are typically know as Tanks or tank-like characters. A tank is more properly defined as a job within the team that the player soaks up damage and protect their team from otherwise painful experiences.

A tank normally has a few characteristics that set it aside from other support roles. Most tanks have high hp and above average defense. They normally have methods of drawing aggresion like Amumu's Bandage Toss or puncturing tauntRammus' Puncturing Taunt. This causes enemies to focus-fire (meaning to target one opponent with the majority of their attacks) the tank and allow squishier characters, such as Twitch, to wreak havoc during team fights.

They also can have methods of CC (crowd control) that puts enemies in a position of fight or die ,and in most cases the latter. These include slows, stuns, snares, taunts, and just generally nasty effects. These are useful for catching "the one that got away" after a team fight or ensuring a gank is successful.

Champions commonly use as tanks have the proper tag signifying this champion is a good candidate for being a tank.

As a side note, I've seen a lot of confusion surrounding the line between tanks and initiators. Initiators are characters who can start fights and typically survive. These are different from tanks in very smalls way, namely survivablity when focused. In the higher elo meta, tank are often forgone for initiators because of damage implications, which i briefly discuss later, leaving tanks in the dust. Tanks, however, are still viable and, if built properly, can carry pretty hard.

Well, first things first, select your tank.

Now, don't go and buy the first champion that pops up with the "tank" tag. This is a bad idea as you may not know what you're investing in. Carefully read over the champion and try to see if it would appeal to your play style. It would be a good idea to try a tank out if was a free to play champion for the week.

Once you've got an idea of what or who you want, go for it. Once you've obtained your tank, you're ready for the next step, learning the role.

First thing you should do as a beginning tank is go for bottom or top lane so as you have a lane mate. Now remember when playing as a tank you are team oriented. While some tanks like Maokai can even be used in Mid during normal games, they still a little shy in terms of killing power.

This is where your allies come in. Since you cannot pack as much punch and take down opponents as well, you hold them down while allies pummel them to infinity and beyond. With this in mind, try to prevent your allies form charging ahead of you, especially from face checking brush (diving in brush to check for enemies).

During lane, it's best to leave harass to your lane mate because you are likely to start a war you can't win when harassing as a tank. Countless times I've attempted this and foolishly died to CC. If you think you can handle it, try it a few times then see if you sing the same tune.

Your main objective is keeping harass and aggro (enemy focus) off of your lane mate while he farms/harass. If you are capable of last hitting(look around for a guide on this one), by all means do so. It can be a large advantage and could get your items down faster and could make the difference you need to win. This should get you through to the Mid-game mark.

Congratulations, you've reached the Mid game stage. For this guide Mid game will be defined as the point wheres ults(ultimate abilities) start coming in.

As you reach this you'll noticed players start giving harder pokes. This is where you get an advantage. If an enemy were to overextend(see a guide on zoning for more details), you can punish him dearly with your taunt or snare. Hopefully your lane mate can join in and you get some damage in.

Be careful with this, however, as this can backfire especially while pursuing.
Between the occasional enemy slip-up and picking fights with he enemy you'll notice several outcomes. The two main types I wish to cover are Kill/Death or Retreat.

In the kill/death outcome one or more of the champions fighting will die and have to re spawn. This is the most favorable/unwanted outcome. It requires them to wait for a re spawn and also trek back to the lane. The return of the defeated, however, can prove dangerous so try to peek at the scoreboard to see if they re spawned. Retreat, on the other hand, requires them to recall/walk back to the base and heal.

Now as a tank, there will be times when you will be able to force these outcomes. Plan your movements, possibly while hiding in brush, and wait for your opening. When the price is right, make your move and initiate. Take careful note of your average outcome as this will help later. If you are currently unable to pick fights, you may try harassment so long as you can take a few hits. This should keep them at bay until the tide turns.
Also don't be as hesitant to push if you have enough map awareness to know there is no threats lying in wait. As certain tanks like Rammus you can potentially excel as a pusher. Once again, be careful as the turret is never a safe zone even when enemies aren't around.

As far as ganking(multiple allies targeting and isolated enemy and vice versa)is concerned, try to keep to your lane when your team is ganking, but when the tables are turned you should try to help if possible. When ganking, try to use your CC to hold the enemy down. When being ganked, use CC to slow the assault or bring it to a stop. Remember, your more likely to have assists than kills,so try not to get greedy. That should cover most common topics until the Late game phase.

The time has finally come for you to shine. Being a tank, you are one of the most vital roles in team fights and since Late game is one team fight after another, you will be very busy. By this point laning is nonexistent so pay attention to where you need to be and try help with map awareness and defense.

While your team has clumped up into a bunch, one or two lanes may be unattended. This are weak points and are subject to a type of sneak attack known as "back-dooring." These are pushed by the other team while your away and can be dangerous to an unprepared team. As a tank you are more suited to be in the middle of the action, but you should have the survivability to defend your structure, like a turret or an inhibitor, defend it, if possible. Watch the health of your structure though as you may arrive too late and be caught helpless. Furthermore, this can also be a bad idea as your team may need you elsewhere. Keep this in mind while playing defense in general.

Another concern pertaining to solo defense is the enemies capacity to overwhelm you. Even if your team is pummeling them into oblivion, then could still beat you with sheer power in numbers. If more than 3 enemies and/or enemies with suppression abilities such as Malzahar or Warwick, it may be a good idea to hold off until your allies can assist you. Them main reason for this is because most tanks are slow. Without Some nice boots like mercury treads Merc's Treads, you easy prey for a faster champion. That being said, if your line of defense, like a turret, were to fail, you're much easier prey for them to catch.
As for offense, you will mainly be pushing down turrets. As tank, your teammates should, and often will, rely on you to lead the way. Being the leader, you must decide whether it is safe to push and how aggressively.

If the enemy team is MIA (missing in action) and you have no idea where they are, it would be wise to postpone your push. If one enemy is defending the turret and your whole team is ready, it would be more understandable to push. On this note, tower diving(taking hits from a turret to kill and enemy or destroy a turret) is also taken into account. If a turret has low hp or your team greatly outnumbers the enemies, diving is possible and would be highly beneficial. If your alone or have half HP,this is not such as good idea. For maximum offensive capabilities, rally your team at your base and begin your push together.

This should be enough to help you net that well sought after victory, aside from team fights but those have their own section located just below this one. Keep these tips in mind and your allies will thank you.

As with all things in League of Legends, the battle can be decided before it even begins.
As a tank it is your responsibility to gauge these team fights before you start them. If the enemy is overpowered or outnumbers the available group, which consists of all competent team members capable of fighting, it may be a wise idea to hold off.
There will be times when you're desperately close to a kill or a turret has a pinch left, but if your team is not readily available it's more likely to be a bad idea to keep going. If you've determined that the team fight could be a possible victory, cautiously engage.

Though it sounds unusual, the best idea would be to rush forward into the masses and target enemies in the middle. At first, this appears to be a horrible idea, but there are two good reasons behind it. As you rush forward, a sizable chunk of players will see you as the first available target and attack you since you're the closest enemy. That is the favored outcome of initiations, however more experienced players will stray from this pattern and make an attempt on your carry's life. If you had rushed to the back, your carry would be vulnerable to these players and you could do nothing to stop them. If you were in the middle, however, you can flank(surround) the enemy and fillet the intruder in a matter of moments.
Remember, if an enemy tank rushes forward, stay at an even level with him. This denies him access to your team and typically halts the enemy advance.

While fighting, keep in mind the morale factor of a team. If the situation appears worse than it is, some enemies will turn tails and run away, as members of your own team would. This is normal and all non-AI players will do this at some point. With all this in mind, it wont always work in your favor and that is normal as well. The only think to do about this is stay calm and try again later. This will happen a fair amount of times so be patient and hope your team can pull through for you.

This is a very good question. Tanks normally should build on a game by game basis. Not one single build will work for every game, and this is true for all types of characters. First start with signature items associated with your champion (try picking one or two that you see commonly throughout the builds on this site). These serve their own purposes and hopefully will aid your game play.

Your next big question is "What is/is going to hurt me the most?" The goal of a tank's item build is to negate a chunk of the damage you are taking for your team. As you play you see various types of champions such as AA Dps. Using your knowledge of this and current in-game experiences, build defenses against what could be dragging you to your demise. For example, if you have a lot of AA Dps like I mentioned earlier, build a Thornmail and some items to improve armor and HP.

One of the most common mistakes tanks(including myself) often make is neglecting their own damage for pure Defense. Not only does this make you an unattractive target but you lose precious damage implication given by those abilities you use for CC. The builds up top include stacking items for various reasons, mainly being to make you more reasonable to attack, but they help tanks, who often don't earn as many kills and receive only half the loot. Don't turn your character into a rock that sits in the middle of the battle and does nothing.

Overall the end of your build really depends on the game you are currently in. Keep this in mind as you play to give you an advantage from knowing what to buy. As I've stated earlier, please refer to other guides for suggesting on what items to use and when.

One of my biggest pet peeves is how easily the term "tank" is used. There are 3 distinct roles that the average person will label as "tank" and move on. These are actual tanks, initiators and offtanks.

Offtanks, with some exceptions, typically are more similar to your AD melee carry than your tank. They deal damage and can take a hit but otherwise have little cc or real benefits to the team. A good example of this would be Garen; his only cc is a silence and if they focus his carries the most likely outcome is a horrible and untimely death. They are useful and can be utilized as initiators in emergency, but are probably best in a damage dealing role.

Initiators, which are arguably similar to tanks, are famous for their ability to start fights with success. The normally have a nice aoe ultimate, sometimes with cc built in, and are capable of dealing damage. However, initiators, again with exception, are not as prone to surviving the fight short of fleeing at the start. The might lack the survivability and due to their damage dealing side job, often require farm to get that extra push.

True Tanks are designed to perform the functions of an initiator at a cheaper cost. This is normally counterbalanced by their offense being crippled. However with proper building strategies, you can manage to earn that damage implication and contribute that offensive aspect back to the team.

In summary,
Survivability: Tank > Offtank > Initiator
Offensive ability: Offtank = Initiator > Tank
Crowd Control: Tank = Initiator > Offtank

Current version: V1.4

History

PROTOTYPE - the only reason I published was so that my friend could see my progress. It will be finished soon enough.

INITIAL RELEASE - For those of you who have waited for this guide, I finally got around to finishing it! I hope you enjoy and that your wait was worthwhile.

v1.1 - technical difficulties wiped out a paragraph of my beginning section and replaced with stuff from the last so I had to redo that little bug.

v1.2 - Spring Cleaning ... in the middle of summer. I tried to help separate the guide and I hope to more on this later so that it looks more presentable.

v1.3 - Slight tweaks to builds and some tips added. Beginning of my rework. More to come

v1.4 - Added new section, took out old.