Guild Banners. The Banner of Cooperation and Battle Standard of Coordination will increase the experience from kills. They both have a 10 minute cooldown, but when you use one, the other is only locked out for 2 minutes. I was very bad about using these, so it might be worth using a macro to drop them on your first attack against an enemy. Keep in mind you must have reputation with your guild before being able to buy these, so new character may have a bit of a wait before picking them up.
As always, I will monitor and update this guide as new information comes in. If I've gotten anything glaringly and completely wrong, just tell me with as much data as possible. The idea is to find the fastest possible leveling method, NOT to argue about how good or bad individuals are. If you have hard data, post it! If you have an idea, let the thread know so we can test it!
 ":"  -  Any time a step ends in a ":" instead of a "." means that the next step is part of the current step you are on.  This generally means the next step should be done while working on the current step.  This means every "start working on" or "continue working on" will end in a ":".  But this is used with other occasions as well, so keep this in mind.

This is also the reason why when I read in WoW forums of people skipping guide sections, due to being too low level I'm not agree and start ranting about it: it'll be a mess syncronizing with the guide and I've seen many people complaining about missing quests or accusing the guide for being innacurate, but not realizing that was their fault since they're skipping and missing a lot of quest chain requirement. Of course this apply if you're following a guide, believe me, it's very frustrating when you remain stuck in a guide section due to the reasons I've mentioned, more than doing grey quests (but they allow to be perfectly in sync with the guide) and goiing here and there to get the pre-requisite quests.
Anyway both got to 110 at around 50h played. I messed up with my Pal by going to Legion once I hit 100 instead of finishing treasures and bonuses in WoD. All in all, if I picked the best zones and was only trying to level as fast as I could, I would probably could have done it in roughly 40h. Note that it would have a been A LOT faster with a Monk as both Ret and Rogues don't really have a decent AoE until 40+ (45 for Ret and 63 for Rogue I believe). The daily also helps a lot. I know that leveling my Monk before the pre-patch was insanely fast. Might be slower with the changes to FoF, however.
 ":"  -  Any time a step ends in a ":" instead of a "." means that the next step is part of the current step you are on.  This generally means the next step should be done while working on the current step.  This means every "start working on" or "continue working on" will end in a ":".  But this is used with other occasions as well, so keep this in mind.
Many people have asked whether we recommend leveling as Enhancement or Elemental. There’s no definitive answer here; it depends entirely on your comfort, your gear options, and if you’re in a group or solo. Enhancement benefits more from Honor Talents in open world leveling, and Elemental has stronger AOE damage for mass pulling. Feel free to experiment with both specs. 

Anyway both got to 110 at around 50h played. I messed up with my Pal by going to Legion once I hit 100 instead of finishing treasures and bonuses in WoD. All in all, if I picked the best zones and was only trying to level as fast as I could, I would probably could have done it in roughly 40h. Note that it would have a been A LOT faster with a Monk as both Ret and Rogues don't really have a decent AoE until 40+ (45 for Ret and 63 for Rogue I believe). The daily also helps a lot. I know that leveling my Monk before the pre-patch was insanely fast. Might be slower with the changes to FoF, however.
“For more than a year in WOTLK I did nothing but raiding and some dailies here and there. I leveled a bit on a few alts and, as all are aware, it cost to support alts sometimes. I did dailies, and LFG quests until the Dungeon finder came along. I did 2 or 3 randoms then logged off if not a raid night. I was bored with the grind of dailies and wanted a change.
“I think [the levelling experience] is a pretty hotly debated topic internally, about how to handle that,” Dawson said in a recent interview with Gamesindustry.biz. “I think we recognize that we’re not giving new players as good an experience as we can, and we do want to focus on how to make that experience better. There’s 15 years of content that people should have the option to do if they want to, but we also want the ability for players to play with their friends quickly. That’s why we developed things like the boost [which automatically raises one character to an appropriate level for the current expansion], which you get if you purchase the game itself. The scaling tech was also a way to help us do that, and you can sort of choose your own path through expansions and story content.”
There are several reasons why this may have happened. First, only a fraction of the players who interact with the auction house buy or sell WoW Tokens. While the value of both gold and commodities plunged relative to real money, the value of gold and commodities remained steady relative to each other. Players who didn’t interact with the Token market could buy the same number of flasks by doing the same amount of world quests, or selling the same number of gems or enchantments, so these sellers saw no reason to raise their prices.
These quests for the amount of time to complete them are not worth a spot that a green quest and above takes up save for questing achievements - this can be finished up later at higher levels (such as for the Loremaster achievement) - or for later rep grinding. Do green quests as soon as possible to avoid the drop in experience when they turn gray.
Drustvar is far and away the hardest Alliance zone, which is exactly why you want to do it first. If you have legendary items, they’ll still be usable, and if you don’t, this zone will still be easier early on than it will be later. Drustvar is also extremely fast and will let you jump out ahead of your competition in other zones, which means fewer players around to take your quest objectives.
In 2015, Blizzard started letting players buy gold from each other using WoW Tokens, to try to control the process and mitigate damage. “Time is money, friend — but sometimes one is harder to come by than the other,” Blizzard says on the official page. “Now World of Warcraft players can use the WoW Token in exchange for game time or Battle.net Balance!”
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