DB and rotation

[Bellafron]

Mod Edit: Moved to Q&A
Ello fellow magis,

I have been wondering about optimal usage for my DB helm. I always use DB on CD since I acquired the helm, however my main concern is regarding the fire opener and using DB. Currently, I am popping sinew at 5, DG at 3, precasting a FB at 2, and then hitting DB at pull. Should I avoid casting DB at all before my opener or continue with my current usage?

[nickseng]

I usually just use DB at the tail-end of the combustion if I have the time.

[Loekes]

Most optimal is popping sinew just when timer starts (doesn't really matter as long as its before pull.
At 2 sec pop DG and start casting fireball at the same time, since DG is off the gcd.
Fish for heating up proc, cast rop and at the last 10% of castbar pop combustion and put in as much pyros and PF as you can. Then at the very end (last 0.5 second or so) use dragons breath, why? since it has no travel time and the pyro you would've thrown here wouldn't benefit from the rune. And the last second breath makes it so it benefits from 5 stacks of pyretic incatation.

And the rest of the fight it should be used on cooldown, prefereably on rune.