For dungeon roulettes (expert especially) trash mob pull...

1. Always Wanderer's Minuet on/Always Foe On during mob pull if you have spell casters
2. Run after the Tank when they begin to gather mobs and when you see them about to slow down, pop Hawk's Eye/Blood for Blood/Raging Strikes (depending if the mob is too much or not)
3. Flaming Arrow the mob pile
4. Wide Volley/Rain of Death till all is dead, if your TP drop around 300, pop Invigorate
5. If the mob pile is still not dead and there is no tp, apply dots, eventually something will crit and refresh your Rain of Death.

Next mob pull you will likely have Hawk's Eye and Blood for Blood on cooldown and if you haven't used Raging Strikes, I suggest you pop that and Internal Release on next pull and do absolutely the same.

For bosses, it's doing one 15-16 skills opener and then it's all priority skills. Always refresh your dots with ironjaws before they fall off, always apply your dots after your buffs and don't forget to look fab af when you do that LB3