I will preface this saying i don't give a rat's ass where this winds up just so long as you remember who wrote this and give credit where credit is due. other tanks with more pro-tips are also welcome.
most of this i tried to convey as simply as i could for tanks who have literally no experience or may actually be new to the game so don't jump down my throat for it sounding too newbish because it is meant for newbs and even for the most hardcore players who might get something out of it(regardless of how uber they might think they are).
1. Pulling mobs:
learning how to pull mobs is the first thing a tank needs to learn. some dungeons and even overland zones have some tricky areas where mobs are cramped into and are "social" to one another.
first i will describe the word "social", tanks use the word social to describe a group of mobs who when attacked will call for help from their friends within a certain range. some mobs have a very small social aggro radius, think of it as having a weak voice so their friends can't hear their call and others have very long social range with a strong voice.
from pulling mobs you will generally see that when you inch towards a mob they will eventually aggro without you having attacked them, that is their aggro radius and generally from my experience aggro radius= social radius as well.
when you run up to a mob without casting or attacking them they will aggro you but they will not shout for assistance from their friends until they are attacked, this is why body pulling is important. anyone casting and even wards or reactives put on the tank from healers can cause the mobs to yell for social aggro before the tank has done anything at all. it is a groups responsibility to control this and not just the tank's.
2. Estimate your enemies:
before even attempting to body pull any amount of mobs you should always be aware of what you are pulling and how many mobs are going to be coming with the one you are focused on. of course social aggro can get you adds but you should know how wide spread a group of mobs is before you even pull them, blindly running into mobs is always a bad idea whether you target them before a pull or not (to save DPS from nuking early and grabbing additional mobs in social range).
when targetting mobs simply target one and look at the target rings on the ground, only linked mobs to your main target will have target rings on the floor. you can play with the options to suit you to help with this. linked mobs will of course aggro when you engage your target.
obviously you will react differently to a large number of mobs in a group than you will to a single mob. inherently large groups of mobs hits for far less and less often than a single ^^^ for example versus 3 ^ heroic mobs. both mobs generally put out almost equal damage but generally the groups actually do more damage than a single ^^^ will but not always.
always <TAB> target through mobs in an area before pulling or manually cursor target them to get a feel for the area, the more comfortable you become and confident in your ability the less you will have to worry about scanning over things before rushing in to destroy it.
remember the layout of mobs and when first body pulling remember how far it was before you got into body pulling range and use that as a basis for social range. you don't always have to body pull mobs but for warriors you really should get used to doing it, ranged or arrow pulling mobs is only really advised for seasoned tanks who know how to aggro mobs quickly, as you progress and fight higher level mobs getting to orange you will find initial aggro become more difficult as the mob outlevels you.
3. Targetting:
selecting targets is simple but not always as simple as you may think.. in EQ2 there is pixel planes than can block your line of sight directly to a mob so you cannot cursor target a person or mob, these areas you should remember because they can be very bothersome.
if you run into an area where you find your cursor not allowing you to pick a player or mob then you can fall back on using your tab and F1-6 keys and escape to clear target. everyone will learn which style they prefer to play in over time, i use a mix of tab and cursor targetting, others just tab to the nearest mob constantly or you can let the next mob in the chain hit you and auto target it.
once a mob dies the next to hit you you will target automatically but you will find high DPS classes grow restless if you leave gaps between targetting mobs. if you allow a space between targetting a mob before the last dies to the next then all those who are assisting you to kill the new mob will lose their auto attack "on" between mob switches, lowering your group DPS slightly and adding more work to maintain it on. it is just more of a nuisance than anything else so try not to slack off in that aspect.
zones like Veeshan's peak have horrible blind spots where tab targetting will completely break and so will cursor targetting. in cases like this you will have to resort to making targetting macros such as:
/tar a glimmering scale or /tar <insert mob name here>
put the macro on your hotbar and spam it when necessary to target a mob you otherwise would have difficulty targetting manually.
4. Soloing:
since it is very likely you will be doing this quite alot... i put it high on the list. zerks are a very capable solo class, not the best but we can hold our own.
self buffs are important, make sure you always are buffed when soloing because a good chunk of our DPS comes from our buffs proccing. temporary potions and stones are also useful if you have extra money to spend. health potions are nice to have for a little bump to help keep you alive on a tougher mob. oilstones and combative/tactical elixirs(when you get to the appropriate level to use them) help improve your solo DPS to help kill the mob quicker.
you will find that more often than not you should ALWAYS be soloing in offensive stance, as zerks we have always lost far too much of our offensive prowess to change to defensive stance and still be effective. in other words you must kill the mob before it can kill you, if you lose too much of your Damage Per Second(DPS) on the mob then you will die before it does. in short our damage output in offensive outweighs our damage reduction in defensive, always has. this will not apply to all mobs obviously but for solo you will find it to almost always be true.
choosing a combination of gear can be tricky but generally i always try to look for gear that has a mix of offensive AND defensive stats on the same piece, this allows for alot less gear swapping to try and maximize your toon for what you are trying to do, you will really only find this type of gear in some of RoK and in TSO and beyond however. previousl tiers had very simple drops for fighters with simple stats.
i will give an example of soloing a heroic zone to give you an idea of what you should be doing as you progress. in Karnor's castle for example on the first mobs in the zone, there is a ^^ and a ^^^ linked at the bridge. cast up turmoil, open woulds, anarchism and hold rage before engaging. i lead off by arrow pulling the ^^ and focusing on the weaker of the 2 mobs first, leading off with bloodshower to knock them down then stunning bellow to stifle them once they are in front of me and then intrusion by spamming all three as fast as they come up to avoid losing auto attack damage. after that initial footwork to bring them down a notch in health focus on the ^^ you are looking at, cycle in your knockdowns/stuns/stifles between each Combat Art(CA).
spread your attacks out evenly, and also toss in defensive abilities like gut roar(EoF achievement tree) as often as they are available to absorb an attack (the final TSO 2 hit stoneskin isn't effective in this zone so don't bother hitting it, if you need it you can't effectively solo the zone anyways). as soon as your 2 temp defensive buffs are down then hit wall of madness, continue using your AE abilities as well as often as you can to slow the mobs down. if you are having difficulty near the end of a fight you can save and pop Adrenaline to finish the mobs off, only use it towards the end of a fight and not the start because if you are out of power half way through the fight then you WILL not be effective at killing the mob the rest of the way down. adrenaline only costs power once it has finished its cycle so use it at the end of a fight to be more useful.
as you progress through KC you will see the mobs tend to be more single target than group, the singles are actually less difficult to kill so if you can kill the 2 mobs at the gate then you will be fine through the rest of the zone with the exception of the named stifles/stuns. when you come to any of the named in the zone simply focus mainly on interrupts (Mock) as often as you can hit it, this will help prevent the nameds from completing the cast on their stifle abilities which can put you down quickly due to your lack of ability to cast temp defensives and deal offensive damage.
check for areas where you can use an invisability totem (totem of the chameleon) to pass by without having to kill anything such as the skeletons just past the rhino pens after the bridge where Rainbrittle spawns. you can use invisability to body pull mobs out of invis areas without adds as well with some practice. with your invisability up simply body pull the mob by moving to its aggro range and move out as quick as possible, your invisability won't break until you get hit by the mob or cast something, you should be well enough out of the area by then that the other mobs haven't seen you.
some players obviously won't be able to do this until they are well geared enough to, i would guess you could solo a zone like that with T2 TSO shard armor and some decent legendary jewelry with the majority of his masters, having the mythical weapon also will greatly help on the linked mobs of 2 to kill them quickly before they can kill you.
when soloing some of the most difficult mobs you will literally be using every ability you have, i have 7 hotbars full of abilities and most of them are used constantly. also when survivability is also in question ALWAYS kill the weakest mob first and as quickly as possible, the less mobs you have beating on you the less damage you will take. burning down the stronger mob first may work well in groups with no survivability in question because it helps kill the encounter quicker by allowing the AE damage to kill the group evenly.
for reference to the T8 versions to lower tiers you can use the list here:
Category:Berserker Spells - EQ2i
this is the end of installment one, more to come later.
pro-tip for today is: "adorn your shit!"
as soon as you have an upgrade piece of gear worth keeping be sure to adorn it. adornments are the final touch to being the best you can be by adding those little finishing touches to your toon.
use this handy tool for quick look ups of adornments for each slot:
http://adornments.h0b0.net/
for a tank in TSO the most important thing to focus on is health/stamina, you can gain a BIG chunk of both via adornments.