It's All About the Damage Baby

Maximizing your DPS
There are a few things I have learned relatively recently that I'd like to share. Some of these will have a decidedly warlock twist but you'll just have to put up with it.

CLIPPING -
Clipping DoT's is the term for casting a damage over time (DoT) spell or ability onto your target before the previous one has finished its complete damage cycle. I was amazed at the change I saw in my dps when I started paying attention to my ticks. A tick is how often a DoT does damage or when a DoT does damage. Not allowing your spells to fully complete a cycle on your target wastes your time and mana, and stops that spell from getting that last bit of damage out. It can also take valuable time away from casting other spells or abilities in the interim, or stacking on what you've just started.
Optimally you want to place your DoT back on the target just as it's wearing off. I am using a mod called in-line auras along with the built in bar timers that come with Bartender, and can see how much longer (in nice large easy to read numbers) each spell has left on it. The number displays right over the spell on my bar along with the GCD timer. Taking into consideration casting time, I will begin casting my next spell as the one that's on my target reaches 2 or 1 second left. For instant cast the time will differ of course. That will insure I get all the ticks out of my DoT and, if done correctly, will keep the damage flowing without missing a beat.

ROTATION
I had always heard about and looked at rotations and tended to follow one myself. Lately, while investigating more in-depth, I have seen a lot of information that leans more toward priorities rather than rotations. I first encountered this when I was looking for prot warrior information.
Since then I have seen it quite a bit and have come to believe that everyone functions on this system. Based on your spec, glyphs and what you may be wearing at any given time, spells and abilities change and fluctuate. Every change in gear can mean your timing changes. Perhaps you have more haste than hit or vice versa. That can make a big difference in how your rotation FEELS. And that is the key. Have an understanding of your spells enough to be able to make those subtle changes as you adapt to changes in your gear or your environment. This is where priority comes in. Priority becomes important when you get into the maintenance phase of your dps. What I mean by that is you're in the middle of a boss fight. You have applied your openers and are now in a state in which you maintain and increase your dps for the remainder of the fight. As DoT's end and fall off you are re-applying and then using some sort of maintenance spell in between your DoT's and your major abilities while they are on cool down. You make that decision based on what ability becomes available next and if more than one does, what priority those need to be re-applied in. Basically, your rotation is your opener. Your priority will determine your maintenance during the fight. This is of course barring other elements occurring during the fight such as moving out of the goo on the floor. Those elements will cause you to reevaluate your priorities during the fight.


RACK 'EM, STACK 'EM AND PACK 'EM
This is twofold. First, if you have spells or abilities which benefit from each other you should know what those are and how they work. It is like buffing your spells. As an example this is my opening rotation for my lock.
Life Tap
Hit my trinket
Corruption
Curse of Doom
Immolate
Conflagrate
And then I begin my maintenance with Incinerate
I have Glyph of Life Tap
Looking at all these elements you can see how they stack on top of each other. Life tap with the glyph converts spirit and buffs my spell power followed by popping the trink which adds even more. I then cast my DoT's which will tick with a greater intensity and CoD will time out with more damage. This will also boost my Immolate. Conflag damage will then get a boost off my Immolate. I have Glyph of Conflagrate which allows my Immolate to keep ticking, while the Conflag itself gives me burst damage and causes Backdraft to start. Backdraft gives me a haste boost going into the beginning of my maintenance phase. Basic priority then becomes which of these come up first, but stacking them correctly as they time out is what makes the difference. Usually this specific casting list comes up in my rotation every 2-2.5 minutes (taking into account reaction time), when my trinket goes off CD. In the mean time it is balancing which of these elements becomes available and stacking them appropriately. Life Tap is kept up continuously, as well as Immolate and Corruption (no clipping). In between is Conflag, Incinerate and Chaos Bolt when it becomes available. In that order to get the most from each spell.

The second part of this is the finish. If you've run in any kind of raid or large group and have been on vent you may have heard your Raid Leader suddenly shout out "Blow all Cool Downs!!". For the longest time I would look down at my spells and think "what cool downs, I'm in the middle of them all already.". For the most part this is true but I have begun potion stacking during the more intense portions of a boss fight or towards the end when your raid partners are dieing and you are racing against an enrage timer.
Once that call is made, as soon as I can I begin the above rotation again with the intention of maximizing everything available. This time along with the Life Tap and trinket I will also pop one of these potions; Wild Magic or Speed. I carry both with me. I also have begun stacking in Flame Cap. Since you can only pop one potion per fight I try my best not to use Health or Mana potions and when in a bind go for my Healthstone first. A Warlock should NEVER be without one.
Throwing in all 4 of my spell buffs; LT, Trink, Pot and Flame Cap followed by the additional haste and damage bonus with Conflag can be awesome. If you can time it on top of Shammy Heroism/Bloodlust you have a winning combination.
The "trick" is to get all the boosting items you can that will stack on top of each other. Flame Cap is a BC herb that I used to use but had dropped a long time ago thinking it was outdated. Truth is it still offers an additional 80SP that I didn't have before. Considering that my large damage spells are all flame based this was an obvious choice to include. It probably would not help anyone else except a Pyro Mage or possibly Elemental Shaman. In addition it is good for 1 minute and can be used again during a single fight after the CD. I can pump out a lot of spells in 1 minute :)

How do I do this?
Regardless of your dps class or spec these tips will help you get more out of your abilities. The first thing to do is to look at your talent trees. Read up on what tree you would like to pursue, then do some research on what talents will help you get the best out of that spec. I have always enjoyed Destro so I had to go out and find the best way to talent and play that spec.
A helpful beginner site is WoW Poplar. This site not only provides the most popular specs but the most popular glyphs, enchants and gems for each one. If you want to get into the number crunching try Elitist Jerks (EJ). If you want more class specific websites go to WoW Wiki. In the search box type in your class/spec such as Arcane Mage or Combat Rogue and down at the bottom of the page is usually a list of websites dedicated to that class or spec. I use The Warlock's Den to get into more class specific discussions.
Second, open up your talent tree. Mouse over and read what your talents do. Moreover, have an understanding of them. So often these days we race to 80, grab a spec that works and then expect to just play it. Without a basic knowledge of what you're doing and how each ability works and is applied you will fail. Case in point, I am horrible on my ret pally. Why? Because I have not taken the time to understand what I'm doing, I just hit buttons. Yes, I admit it. That's her off-spec so I don't pay much attention where I should.
Third, understand your rotation and priorities and why. You have to know what ability benefits from another before you can apply them correctly. Again, refer to my ret button-mashing mentioned above.

I know some of this is basic information, and perhaps common sense. I am one of those people that has to understand the pieces to see the whole picture so it took me a while to really get it. I only hope that some of the knowledge I've gleaned can help someone else along the way.