Here's how my buddy Kitau did it:
She partied up with her fiance Holymoley and talked with the event mog at the Windy Woods gate. Once the mog was finished explaining how to play, they were teleported to T. Canyon. Invis and sneak wore off rather quickly, (30 seconds of so?), and didn't give any warning message that she remembers. I guess that's only there if you get teleported right in front of a Yagudo.
If that happens to you, MOVE! (There's a lvl 1 restriction, so you will lose the fight.)First thing they did was get together! <3 Then they rested, and after a few seconds they each got a message "the compass is pointing southeast." They followed the directions and paused every once in a while to re-check the direction. Kitau's compass led her to Holy's check-point, and vice verca.
When they checked their respective points, they each found a doll. They then used their Windy Woods glyphs to teleport back to the event mog, traded each other their dolls, then traded them to the mog. Obtained item: Onago Yukata, Rare/Ex Female Only, Def 1, Dispense: Muteppo!
They put on their spiffy new shirts and talked to the mog again. "I see your wearing your Onago Yukatam," said the mog, "Get ready for a real challenge!" They were then teleported to the Highlands. This time the compass gave an interesting message when they rested: "550 yalms... 680 yalms...." (If you stay rested the message will come up every few seconds.)
After much confusion, she eventually figured out that HER compass was giving Holy's distance to HIS checpoint, and had nothing to do with her distance to hers! They found that the best strategy was to find a safe place for her to rest and call out the numbers to him until he found his, then he rested till she found hers. Teleport back, trade dolls with each other, trade with mog, obtain item: Onnagimi Yukata!
By the way, if you check the wrong check-point and "find nothing," you have failed. Don't bother continuing, just return to the mog and start over rather than waste time. Some check-points are right next to each other, so be careful to wait till you get the "0 yalms" message. Another idea is if you have a high lvl friend or two willing to follow you around and kill the beastmen that stand in your way, it would be a lot easier.
Both shirts dispence 99 of it's fireworks once every 160 hours or something... and both kinds of "fireworks" are FUN! (One's more like a 10-second costume.) My fave thing to do is to use the longer-casting one then immediately use the shorter one and run in circles! =^_^= Some like to use emotes like /kneel to get the one firework to shoot up rather than out. Have FUN!
P.S. Forgot to mention oils and powders don't work. >.<