Adventurers of Van'adiel love to run around town in their hard-earned gear, showing off their achievements in the game. So why not start the quest that will reward you with one of the most 'fashionable' head pieces in the game to show off around town, that also is a wonderful piece to macro in for situational use? The truth is, Maat's Cap is a wonderful hat to macro in for weaponskills, SATA, straight tanking, jumps, cures, nuking, etc. and the added enchantment of Ru'lude Gardens warp isn't bad either. So why doesn't every player have this hat? The versatility and potential of this hat would make it a wonderful addition to every adventurer's wardrobe, and the fact that all jobs can wear it entices even the laziest leveler to level up some jobs to be able to equip the hat. So what? How do you get it? It's simple, to obtain Maat's Cap, you must complete the quest "Beyond the Sun", which is accomplished by defeating Maat with Bard, Beastmaster, Black Mage, Dark Knight, Dragoon, Monk, Ninja, Paladin, Ranger, Red Mage, Samurai, Summoner, Thief, Warrior and White Mage in the 70 cap quest called Shattering Stars.
So it's simple, right? Beat Maat on every pre-CoP job, and then he gives you his hat. It's a lot harder than that: First, you must have these fifteen jobs leveled to at least 66, which is the minimum level to enter the battlefield "shattering stars" , in order to even begin this quest. Second, you actually have to beat Maat for it to count towards your progress in the quest. You can repeat the battle as many times as possible until you actually defeat him, but defeating him can be hard, depending on the job. At level 66, it's possible to beat Maat, yet it usually requires capped skills, expensive gear, and taxing meds and food. Even with the best gear, food, and capped skills, a win isn't guaranteed at level 66, so it would be smart to take into other things such as moon phase (if you're leveling Summoner, for example), the particular day (for Black Mage, Red Mage, etc.), and what time it is (for Ninja). All of these aspects will help you beat the relentless Maat the 15 times required for your hat.
Maat's Cap will be a very arduous piece of equipment to obtain if you are the perfectionist that enjoys wearing the most expensive, hard to obtain equipment for whatever job you're leveling at the time. If this is the case for you, and you love playing Final Fantasy at your own slow-paced speed, then trying to speed your way to a Maat's Cap won't be any fun at all for you. If this applies to you, then simply level these jobs at your own pace, getting the jobs you enjoy all the way to 75, and the jobs you don't particularly care for to 66, fighting Maat only when you feel your character is able to defeat him. If you play like this, don't expect your Maat's Cap any time soon, if ever, but that's just how some people are. For you more fast-paced players that can get a job to 75 in three weeks, the thought of a Maat's Cap is more viable, and the reality of actually having one is a reality that can actually happen pretty soon with some hard work.
Here's some pretty decent advice when starting Maat's Cap quest and not knowing where to begin: Unlock (if you haven't already) all the extra jobs at the same time, and level all of them to 20 before you do anything else with them. This is made possible, because, through level 20 most gear is interchangeable between jobs, separated only by mages and DD's. So pick up some versatile, cheap armor, and spam through every job through the dunes, and decide which jobs you want to do from there. As disgusting as leveling 15 jobs through the dunes consecutively sounds, after you finally finish, then you'll never need to go back through that step in this quest again, and you'll thank yourself for doing that later, I promise. With every job unlocked, and every job at least level 20, the 'hardest' part of getting every job to 66 is finally done - with the horrible events that happen in the depths of noob-infested Valkurm Dunes, Qufim Island will be very promising -- and now it's time for some classic, grinding experience points parties in FFXI.
If you're serious about obtaining your Maat's Cap, then it would be very wise to conserve and recycle Gil as much as possible, spending large amounts for items only when you absolutely have to. The good thing about leveling up many jobs at once is that a lot of jobs typically wear the same gear at those respective levels. A Scorpion Harness, though expensive, can be used by almost all of your DD jobs that need accuracy, so it's wise to purchase these expensive, yet necessary items. For job-specific gear, such as Scythe's, Great Axes, Long Swords, Guns, Bows, etc. that you're sure you'll only use once, it would be wise to re-sell these items as soon as you level out of them, to effectively recycle your Gil. This will ensure that a little bit of Gil can go a long way, and also that your inventory slots won't be maxed out on unused items.
There are some jobs, Summoner for example, that has essential items, that are unfortunately rare/ex, and some time must be spent to obtain them. Unfortunately these items are pretty much essential to the job, and time must be spent in order to receive them. So you can either take the time to receive these items the same day you unlock all the jobs, as you aren't even leveling them up at this point, or you can do them while you're completely exhausted from leveling, and need to do something else before you collapse from boredom. Some necessities that can be received fairly easily (and free!) include: some ichi spells for your ninja, all the summons, Carbuncle's Mitt's, Evoker's Ring, for Summoner, RSE for all jobs, and selected AF, there are some items you simply must get for survival in the experience points party world.
I hope this guide hasn't scared you off from trying to obtain Maat's Cap, rather, I hope it has served as a source of inspiration for all aspiring adventurer's out there wishing to obtain one of the most powerful headpieces in the game. So now it's time, absorb what I've told you, kiss your social (or endgame) life away, and prepare to be the envy of all your friends.