This is the most common setup that we've used to beat her. Ambuter covers it all here in detail, it's very similar to ours so I'll just copy-paste his because I'm lazy :P. Just some learning points we've taken from our fights.
*In order to avoid a lot of unnecessary heartache, she must be brought down to less than 40% health in order to avoid Phase 2 and move on to Phase 3. Invest in your BLM gearing and skill to get that DPS up, food and pots help.
*DRGs should ensure that keen flurry and ring of talons is up after her last jump during Phase 1, as there will be substantially more plumes to take down. Assigning primary pillars to each "plume killer" helps avoid wasted AOE skills
*DRGs save Dragonfire Dive for Chirada in the event that a BLM goes down during a clone wave.
*Go get the GC tonic/expectorant, each person have one of each on their person, it's an instant raise. No brainer here. 215 seals total for both.
*PLD covers your highest DPS BLM during clones. There will be more than enough people on Suparna, you can't afford to lose that BLM with this setup.
*PLD voke/flash Suparna as quickly as possible. If she goes for and kills the WHM, it's a wipe. Hate may get pulled off of the PLD by the DDs who are on Suparna, that's fine. The name of the game is to get her attention first to keep her off of the mages.
*Don't face Garuda or the clones at the rest of the party...please?
*When clones die, DPS Garuda as best as you can within the time-frame, but after one or two WS combos, save that TP. You'll need it to AOE the plumes for South Winds, or to burn down the next set of clones. Throwing weapons help with TP generation in between auto-attacks.
*If Garuda is less than 20%, we usually just ignore the clones and burn down Garuda. Be wise about this, as this depends on your party's own level of DPS.
I see a lot of concern on the thread about "how much DPS do I need". I don't have an answer to that yet, but next time we fight I'll take note of it. I'm sure that a lot of people may disagree, and others may side with me when I say this, but I feel that these are the necessary elements in any high DPS BLM, in order of priority:
A well-geared/skilled tank > BLM Skill > BLM Gear > Food and Pots.
*Get protection. You've got to have a tank that can QUICKLY generate and hold hate. A BLM with all 5 meld/BIS gear with a high degree of skill won't produce much DPS if they're dead due to pulled hate, or if they have to hold back their DPS the entire fight. Need a tank that can support that level of DPS. Overall level of potential damage is proportional to the amount of enmity that can be generated by the tank.
*Get skilled. Doesn't matter how great your gear is if you can't quickly and efficiently move through your dmg/hate rotation.
*Get geared. A highly skilled BLM with great gear will outperform an equally skilled BLM with nothing but full AF or worse. It's a numbers/stats game when the skill is equal.
*Get support. Food, potions, and songs all help to make a great BLM amazing, but they aren't much without a good foundation.
This turned out to be a little more lengthy than I intended, but hopefully it helps some of you out. Cheers.