Im quoting myself here now..as im lazy and dont wanna write it all over again 
This is how i do it..mostly anyway...if im in the MT group or just normal group instance.* GroupWard* SingleWard* Bolster on tank*Ancestral Sentry on tank.- Wait for pull......* Starting to cast GroupWard again as the tank runs in to cover the first hit that the mob does to the first groupward.* SingleWard* SingleTarget Debuff - ( one of the attack reducer )* SingleTarget Debuff - ( one of the attack reducer )* SingleWard ( If needed )* GroupWard* Encounter Debuff* Encounter Debuff
.......repeat...
I think that is roughly the way..ofc it depends on the mob..how hard he hits and the amount of healers in raid.But yes I try to keep the Tank warded until I think the other debuffers have a chans to trow in some debuffs...and if my recast-timers are still ticking im doing my debuffs between the wards.I keep watch in the "spell window" to see how fast my wards are ticking down too...then I can see if the mob is starting to be quite debuffed too.
If im in the OT group it abit diffrent.* GroupWard* SingleWard ( on my OT )* Bolster on MT* Ancestral Sentry on MT* Wait for pull......
* SingleTarget Debuff* SingleTarget Debuff* Groupward ( incase my group took alot of dmg on pull or its low )* Encounter Debuff* Encounter Debuff* SingleTarget Heal on MT if needed.* Heal and Cure and stay ready with SingleTarget Ward if the Defiler goes down, or perhaps has a Curseetc and he / she cant do her job for a sec.* Keep my own OT ready and fully warded incase he needs to Offtank stuff or tank goes down.
* If its a NamedFight im not focusing on doing dmg at all...if its trash I go in and smack unless my group is taking dmg.I NEVER prio my dps before my groups health.
I hope I havent forgotten anything...this is how I mostly do it...im sure there are lots of other good ways too 