Post by Guildmaster
Use this spec:
http://www.wowhead.com/?talent#cxoZ0eVoZx0ci0cIhedVhszIf you are having problems with your mana, you can switch to this, which will lose a few percentage points of dps but will keep your mana bar full on most fights:
http://www.wowhead.com/?talent#cZ0eVoZx0ci0cIhedAhsu(Specifically, Aimed shot is generally not worth giving up what you can get for the talent point elsewhere for PVE; Missing Resourcefulness means that your Black Arrow uptime goes from 15/24 to 15/30: .625 -> .5. )
You want to stay at or right below 8% hit (This is the current hit cap for hunters). Anything above is a waste.
Oh, and change your trap glyph to Explosive Shot.
For most gear, just gem straight agility once you're at the hitcap (ignoring socket bonuses. Most of them aren't worth what you lose). Gemming crit rating is usually a bad choice.
The exception is: If your metagem requires something other than a red gem, make sure to pick the best socket bonuses to use for the off-gem, and go with a Crit/MP5 gem in a single slot if you can.
Finally, make sure you're using the right priority queue: (Not really a rotation)
Hunter's Mark > Kill Shot >SERPENT Sting > Black Arrow > Explosive Shot > MultiShot > Steady Shot.
Try to stand still where possible for the Sniper bonus.
If you proc Lock & Load, alternate an different shot between the Explosive Shots, so that you don't munch half of the damage from them.
Hope some of this was helpful.
(Fixed embarrassing typo pointed out by Helvorst (thank you))