(This Post Is A Draft, But I Felt I Should Share What I Have So Far.. Before I Finish It and Correct It)
Leveling in World of Warcraft used to be a pain in the rear but thanks to things like refer-a-friend, gear and elixirs that grant extra experience, rares, treasures that give experience, the Darkmoon Fair, holiday events, world events, invasions, some gathering professions, and so on leveling add in account wide flying in WoD and Legion leveling from 1-110 is so easy, even without flying or gear you can always get a higher level player to power-level you through dungeons from the low level of 10.
Or for an outrageous amount of $60 you can boost a character to level 100, if you do this to yourself a favor and level to level 60 first and pick two profitable professions like mining and blacksmithing, skinning and leatherworking, or maybe enchanting and tailoring. It really doesn’t matter you can pick whatever but if you don’t want to spend weeks levels each one or spend a tons of gold doing it fast then this gets you to 700 from the start.
I have almost all of the BoA gear used for leveling from 1-100 and once I toss some enchants on them or send them to an alt I usually solo the first dungeons you can get into with most classes Horde is easy Ragefire Casam, Alliance you’ve got a bit of a walk for the Deadmines, run these until 20 or once you hit 15 que for randoms, but run these between ques.
Grab riding, Alliance head to Stormwind at around 22 and solo Stockades, or have a friend run you until 30. Horde head to Shadowfang Keep until about 26, both factions can move to Scarlet Monastery and Scarlet Halls for some easy level if you have someone running you, you can reach the mid to upper 30’s rather quickly… I don’t really recommend soloing these… it can be done but the time it takes it not worth it.
With the BoA gear and a couple of potions or xp buffs having someone run you in dungeons makes leveling go so fast, but I would save the potions until your level 58 or so most don’t work past level 98 providing you can even get your hands on the potions, the drop chance sucks with a capital S! There are a couple of rares that will drop it in MoP and some in Nagrand in WoD that can drop it, 300% xp for a short time… 15 minutes if I remember correctly.
It may be hard to get hardly ever any on the auction house so unless you have a level 100-110 the better geared the better I would forget about the potion. You can farm them with a level 100 with crappy gear but it takes a while to kill the ones in WoD, at 110 they are rather easy, and at iLevel 860+ it’s super fast if the mobs spawn and you get the drops you need, even with server hop it’s a royal pain to find them up.