As Duty Finder gets worse and worse since the people who are fed up with how slow DF runs are start joining PF runs, PF quality is now also slowly being diluted. It's not OK for these "speedrun, use good essences/actions" PF runs to take 25 minutes. When several people in such parties are using useless essences like Templar and useless actions like Protect, it's clear that people either don't know what to bring or are intentionally trying to leech off of these parties. If you don't want to contribute meaningfully, don't join PF and leech off these parties.

I'll give some of you the benefit of the doubt, assume you don't know what to bring, and explain what to bring. (The leechers can just go away though)

TANKS:

If you're main-tanking, bring:
Essence: Spirit of the Indomitable
Actions: Banner of Honored Sacrifice + Blood Rage (especially good on WAR). Alternatively take Banner of Noble Ends/Lost Font of Power (can only get 2 uses).

How to use Blood Rage on WAR:
You accumulate Blood Rage stacks by using your gap-closer, Onslaught. Once you use 3 Onslaughts, you enter Blood Rage, where any skills, including Lost actions, get a CD reduction of 75%. This includes Inner Release. The moment you enter Blood Rage, use Banner + Inner Release, and just spam Fell Cleave. The CD for these two skills will come off before Blood Rage is over, so use those a second time. This will give you a third Inner Release 24 seconds later outside of Blood Rage. Same thing works for DRK's Delirium.

It is possible to chain Blood Rage by using a Blood Rage within the Blood Rage window (make sure to pop a new stack of Blood Rage from your holster).

If you're on PLD/DRK/GNB, make sure to space out your gapclosers enough so that you get 3 gapclosers in before your Blood Rage stacks fall off.

If you're off-tanking, bring:
Essence: Spirit of the Irregular (best). Or Indomitable/Martialist.

How to use Irregular
For bosses before Trinity Avowed, use 30% mitigation for every raidwide. For the last two bosses, use 40% mitigation for every raidwide. It might be hard to use 40% mitigation for every raidwide on The Queen if you phase early (which is almost always the case in PF runs). In that case use your invulnerable skill (such as Holmgang). If you're using Blood Rage, fitting mitigation into Blood Rage windows is a good way to get mitigate more. It is completely possible to use Irregular and survive with zero healing on Warrior while also using Banner of Honored Sacrifice with good timing of skills within Blood Rage. If you die too much, do your healers a favor and swap to Indomitable/Martialist.

An Irregular Blood Rage tank can contribute 30k-40k. If you're chaining Blood Rage, you can expect 60-70k on a warrior.

Finally, as a tank, you can also scout for traps for the raid. Just use your invulns and run forward, popping traps along the most common path used by people.

HEALERS:

If you're the only healer, and you're not confident in the other casters, bring:
Essence: Spirit of the Aetherweaver
Actions: Seraph Strike / Font of Magic / Lost Chainspell

Tip:
You can pair Thin Air with Seraph Strike every third use.

If there are a lot of healers, talk with the other healers, make sure there's at least one healer/Cure 4 caster in the party, then bring
Essence: Spirit of the Profane
instead.

This setup is the easiest to contribute decent damage to the raid (20-40k) without having to think about what to do. That being said they are nowhere near as good as actual DPS players maximizing their potential.

Ordained + Chainspell does not beat Deep Aetherweaver, and especially not Deep Profane.

MELEE DPS:

Essence: Spirit of the Duelist
Actions (Render): Rend Armor + Banner of Honored Sacrifice
Actions (Non-render): Lost Font of Power + Banner of Honored Sacrifice

No matter how you put it, Beast + Assassinate is simply subpar to Duelist. Honored Sacrifice is the go-to as it is buffed by Duelist. Please stop trolling people by telling them Beast + Assassinate is better than Duelist + Honored Sacrifice.

How to use Rend Armor
Call out whether you're first rend or second rend. If you're first rend, use Rend immediately in the first GCD (you can just gapclose with Rend then start your opener). The 0.7s clip to your opener is worth less than 10% damage for everyone on their first few GCDs. You're trolling if you're using Rend in the fourth GCD or something because you can't find a weave spot in your opener. If you're second rend, pay attention to when the first rend drops off, then use your Rend (@ 30s). Then just use Rend on cooldown.

Every raid only needs two renders. Bring Font of Power if you are not a render.

PHYS RANGED DPS:

Essence: Spirit of the Fiendhunter
Actions (Dervish): Font of Power + Dervish
Actions (Non-Dervish): Font of Power + Banner of Noble/Honored

Just use Dervish on cooldown. A physical ranged DPS is also best suited to scout for traps for the raid. Having one person swap between banners and perception is ideal to limit pointless deaths, if the tanks are not using their invuln to scout for traps. To do so, make sure to stand as close to the exit before the boss dies, then sprint and peloton forward and use your Perception.

CASTER DPS:

Flare Star user:
Essence: Spirit of the Elder/Ordained
Actions: Flare Star | Font of Magic (if Elder) + Ethers / Chainspell (if Ordained)

How to use Flare Star
Call out if you're the Flare Star user. Note that you need 9000 MP to use it, which makes BLM a good class to use Flare Star. It is possible to use Chainspell and Flare Star if you're in Ordained. You cannot use Chainspell and Flare Star in Elder as the cost will exceed 10000 MP. Try to use Flare Star a few GCDs in to snapshot as many buffs as possible. Then simply refresh Flare Star every minute.

If you're on Elder, you will want to use Flare Star within Font of Magic and make sure to have an Auto-Ether buff on. If you don't bring ethers, there's a chance your Font of Magic will end prematurely after using Flare Star, even if you're a BLM in Umbral Ice. This setup, if used to its maximum potential, does the highest damage if you are chaining actions by popping Chainspell during the Flare Star GCD (5 seconds). However it is of course prohibitively expensive.

Rather, Ordained + Chainspell is better suited for daily use. Simply use Flare Star within the Chainspell window. It is optimal to clip Flare Star at 90s to get the second Chainspell buff, and so on. You don't have to juggle ethers with this setup and it'll do more damage than an Elder who's failing to maximize their damage during Font of Magic by fumbling ethers or whatever.

Cure IV user:
Essence: Spirit of the Elder
Actions: Cure IV (one per party), Chainspell/Font of Magic

Others:
Essence: Spirit of the Elder/Ordained
Actions: Font of Magic + Chainspell

Use Cure IV every minute to keep up a 10% bravery buff on everyone. You can also replace a healer by being the main healer using Cure IV, which will allow all healers to go Profane. Communicate this in advance.

If other casters have already picked Cure IV with Elder and someone has picked Flare Star already, just go with Font of Magic + Chainspell with Elder or Ordained. If you're on Ordained + Chainspell, make sure to align Chainspell with your burst window. If you don't, Elder + Chainspell is strictly better.

Finally, one caster also needs to bring Banish for the Phantom. I recommend swapping into and out of Banish, though it costs a bit more.

There are of course more advanced/costly strategies, such as using Excellence, using Focus + Slash on Machinist at the start of a boss then switching to Font of Power, and they can do insane damage. But if you just want to meaningfully contribute to PF Delubrum runs without being a burden these are a good starting point. Just please stop bringing useless things like Protect II or Bubble.