So I recently dinged my alt Rogue 90, and realised my ilvl was something like 420, and was not looking forward to doing dungeon after dungeon after dungeon to get the gear to go into LFR.
So obviously, if like me you are even too undergeared to get into heroics, have a look at the list of items that are linked to the fortune of pandaria achievement, it may seem like common sense to some, but always make sure to replace your lowest ilvl items first, therefore increasing the amount of ilvl you gain the most.
Onto my main point, when farming heroics, yes, you may pick up gear from time to time, but the main way I have increased my ilvl is putting to use the heaps of justice points you get. Rather than spend them on the crappy Justice point blues at Townlong steppes, go to Stormwind, or Orgrimmar and go to the cata justice vendors, The justice trade goods vendor there will give you 250 honor points for 375 justice points. So usually i can get 250 honor from each dungeon (each boss drops 120 if you have a lvl 25 guild)
You then go to the Honor and justice vendor and start replacing your useless low level greens and blues with pvp epics. though some of the stats are wasted on resilience and pvp power, they were still a lot better than some of the junk i was wearing.
It's the day after I dinged 90 and I'm just about to go into my first LFR
PS: Don't forget to go to isle of thunder and do the Palace troves dungeon for some coins of good fortune
PPS: I hope this isn't a repost, I had a search but I couldn't find anything
After looking at my wall of text I decided I should condense it :P
Farm world treasures (ilvl 450)
Farm Heroics
Trade in justice points for honor
Buy ilvl 476 pvp gear
???
Profit