Alright ladies and gents, time to put together a Simcraft guide. I'll be modeling my character, Zagam-US, Mal'Ganis, as an example in this post. Any questions about modeling should be asked and resolved in this forum.
I'm going to skip most of the tutorial on how to change options and such in Simcraft because they wrote their own guide on how to change things. I'll just show what options I use for the most realistic approach to using Simcraft.
Iterations - 10000 (used for higher level of accuracy)
World Lag - low (I run at about 35 ms)
Length - 450 sec (fights vary in length, so use the appropriate time if you care about one particular fight)
Vary Length - leave at 20%
Fight Style - Ultraxion (I use this because no fights in WoW anymore are a true Patchwerk style type fight. You're almost always taking damage and having to do something small. This is the smallest interruption style, so I feel it's the most appropriate)
Player Skill - Elite (should be used if you know your class extremely well and make no mistakes in your priority while playing)
Leave all others at default.
Leave all default options up unless you want to model your own raid where you are missing certain buffs. Good if you are missing spell haste and want to see how awful missing out on it is.
This is how you will find your specific scale factors. Check Intellect, Spell Power, Hit, Crit, Haste, and Mastery. Nothing else matters. Leave options at default.
This is your scale factors visualized with a graph. Moderately useful, but nothing special.
This is where you can model your reforge options for a stat you care about. Not really necessary with scale factors and adjustments made.
Battle.net - use this to import directly from Battle.net
CharDev - not reliable, missing items
Rawr - not experienced with this option
Sample Profiles - this is preloaded with BiS normal and heroic profiles for each spec. Import one of these and modify to your liking.
This is the bread and butter tab. This is where all the magic happens. If you import a pre-loaded profile, this tab will automatically populate. If you import your character, it will load everything. If you import a pre-made character, it'll be automatically set up for you. That's not why we are here.
Once you import your character, head into this tab. You'll see a bunch of garbage that'll make sense very soon.
This will autopopulate a lot easier if you import your own character. For those who wish to do this at work, download a pre-loaded character and just replace what you want. For example, I think the default race is Dwarf. Change to whatever you want. Note: Because I changed to an Orc, my racials changed, but the Simulate tab did not update...we'll get to that in the next section. Some races auto-update, but on command actions do not.
This is your buffs you have on you. You can delete the flask or change food if you want to accurately model your character. Pretty simple stuff here.
Now that is where things get crazy. Basically this is your character's priority list in Simcraft. What this means is the top action has first priority. So you can see that the very first thing that should always be checked is Curse of Elements. The absolute last thing you can do if you can't do any of the above (out of mana, nothing to attack, etc.) is to cast Life Tap. Everything else in between is ordered in priority. You can modify this if you think you're onto something (I typically remove Fel Flame because it sucks). This list uses the Doomguard at the beginning...for fights like Elegon, you could model it by changing his line to include the following: if=target.health.pct<20.
This would be a good way to see if changing the priority on your Doomguard changes your overall DPS. I'll save you some time...it doesn't.
Note: the line that adds Blood Fury had to be manually typed in for me because I changed "Dwarf" to "Orc." Similar changes would need to be made if you wanted to be a Troll. The line would look like this: actions+=/berserking
This is how you can see how much racials affect your DPS in a theoretical world. If you're contemplating changing what your character is, just import, change race, modify accordingly by adding your on use, keep all other things the same, and simulate. Note, for Undead, you do not need to add anything. Touch of the Grave automatically comes out in the report.
Same thing as above except this is your priority during AoE. If you want to see if Rain of Fire does more than Seed of Corruption, remove Seed and add Rain of Fire. Hint: it doesn't, but this is where theorycrafters find that out!
This is the section where you modify your gear. I'm modifying stuff on my own character, so I'll show you how to do it. Let's say you want to test out a pure haste build. Let's look at the helm line. See the part that says 'reforge=haste_hit'? We're going to modify it. Change it to: 'reforge=mastery_hit'
Syntax is SUPER important. Don't use a period instead of a comma or forget an underscore. I'll explain an item for better clarification...let's look at my belt. Where it says gems, what that means is I have a 320 mastery gem, another 320 mastery gem, and a 160 mastery/160 hit gem. The extra 120 haste is the socket bonus. If you want to try a haste build, replace 320mastery with 80int_160haste or 320 haste. Just separate each stat with an underscore. Same thing for enchants.
Let's say you want to see how much of a DPS gain you'll get from upgrading your trinket. See the line for Light of the Cosmos? The very last part of the line is 'upgrade=1'...this automatically updates the stats during simulation. This is how I formulated the trinket list on these forums.
Let's say you want to switch a trinket out. Perhaps you want to switch out Relic for Essence of Terror. All you'd have to do is put the following: trinket1=essence_of_terror,id=86388. The ID is the wowhead identification number. To get this, just go to wowhead.com, type in the item, and find the 5 digit number in the URL. That's your magic number.
That's it! After you get everything set up, hit that Simulate button in the bottom right hand corner. Allow some time (it is doing 10000 fights of 450 seconds each!), about 3-4 minutes depending on computer speed, and your results page will pop up. Click through the various tabs to find out your stats, priority list, action list, buff uptimes, etc.