What's the fastest way to level?

[Terin]

Honestly, I have two characters who I'm debating about making my "main", but as awesome as some of the limited-time event rewards are, I'd like to try leveling both of them as quickly as possible -- at least, for their base Classes anyways. My Miqo'te has taken foooooreeeeverrrrr to make level 15, as I'm been playing as a bit of a completionist so far, doing every quest I come across. I feel like there might be a faster way to level, though, and if so, I'm curious how I might do it?

Also, of the base Classes, does any stand out as being noticeably faster or slower for leveling? I'm currently playing a Pugilist, and the other character is a Gladiator, but if there's another way to level faster, I'm fine with switching, as well. As much as I like following the story, I'd rather be prepared for whatever cool stuff Squeenix has in store for us :P

[Urthdigger]

Do quests, especially from your guild, and do your hunting log. That's a fairly quick way to get up to 15.

[Terin]

Makes sense. Is there something particular that happens at 15, though? Should I just continue doing class-quests, or are there groups that I can join?

[Enkidoh]

Main story quests also give a lot of exp as well, and importantly unlock certain gameplay and content elements (Inn rooms and levequests/guildhests by completing the level 10 story quest , airships and the Vlybrand-Aldenard ferry with the level 15 story quest, retainers with the level 17 quest, personal mounts at 20 etc). Main Story quests can be identified by a special Meteor icon above the relevant NPC instead of the usual exclamation mark in a speech bubble.

[Karja]

Before the the big patch the fastest and easiest way to level was to do fates in a fate group. While fates are still a good way to level on my server the amount of people doing them is lower than before and thus it takes longer to do them. My first class took quite some time to get it to 50 because i did many quest.
After the big patch i leveled a WAR to 50 in a few days going for 5 levels day after i hit level 30, getting a character to level 15 doesn't take much time, just do the Hunting Log and any Fate you can do.
After you hit 16 you should do your low level roulette everyday. Since the patch doing instances are good exps and tanks normally have zero wait times. Another good way of making exp is to do escort leves. For example i did the leve "we are missing one of our naturalist" about 60 times (level 45+). If you ignore the mobs and just run through it with a difficulity level 49 it took me under 2 minutes and i got around 18,760 exp each time (levelups to 49 is 500k exp).

[Magea]

Dungeons now give very good exp. For instance in Stone Vigil at lvl sync I was getting 1800 exp per kill. When waiting in duty finder do leves or fates. I personally save my leves for crafting as I notice that it is becoming more expensive the higher I get. Best advice, find a good Free Company that has EXP bonus up when your lvling, eat food 3% extra exp adds up over time, don't forget to rest, Have Fun!

[Maero]

Fastest way other then leves and fates would be chain kills, you can easily level this way.
Some enemies (usually same lvl or slightly higher) once killed starts a count down, the more enemies you kill within that amount the more xp you get. I always start off the different classes this way.
Hunting log as well but you level faster from the chain kills

[MisterChubu]

i've found like the others have said is that questing and jumping into lowbie fates is the fastest way to hit 15. Then by that point your storyline should send you to the first dungeon and from there just quest and stay queued for dungeons as the exp in earned from them has been boosted a lot, post patch 2.1.

[whiskeybravo]

I would recommend getting one class to 50 first for 50% exp bonus on your other classes. Leveling 2 at a time will feel like forever.

[Bixby]

I would recommend getting one class to 50 first for 50% exp bonus on your other classes. Leveling 2 at a time will feel like forever.

You don't have to get to 50. You get a flat 50% as long as you're under your highest level, even by 1. The in-game help was wrong on release, don't know if it's been fixed.