The Tricked-Out Thinking Cap

You can skip the first seven clues and go straight to the 8th clue at:

/way 64.7, 53.7 beneath the waterfall

The clue in the seat of the aspects is not up top and is not even fully inside the lower building. It's in the entrance corridor. I spent forever looking up top and inside. Just hope to save someone else some time.

For hunting down clues (the arrows):
They give you a vague direction and coordinates, when you click on them. e.g: EAST (16,-2)
You can the re-equip the Thinking Cap (use the toy again) to calibrate it to (0,0) and when you mouseover the buff of the cap, you can see, where you are right now.
First number is: West(-) / East (+)
Second Number is North(+) / South (-)

So (16,-2) is 16 to the east and 2 to the south.

It is fairly easy to find all the arrows then.

Hope this helps :-)

Locations of the arrows for the lazy ones:

Spoiler

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• First Clue: 26.6 54.1 at the wall near Fangli Hoot
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• Second Clue: 10.0, 56.3 on the floor in front of a bookshelf
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• Third Clue: 39.9, 64.5 on a create
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• Fifth Clue: 36.2, 71.2 on the floor in front of the Alchemist's Lab Bench
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• Sixth Clue: 44.1, 58,8 on the roof of the AH
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• Seventh Clue: 38.0, 49.2 On the floor near the Obsidian Guardian
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• Eight Clue: 55.2, 43.3 enter of the Seat of the Aspects → at the first fire on the left side
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• Last Clue: 64.7, 53.7 beneath the waterfall
• 
  

Like smoere said: you can go straight to the last one, if you want