Fashionista: Shirt

If you're looking to smash this out as quickly as possible and spending 750 gold doesn't bother you, here's a quick way in 2 minutes you can grab this achievement:

Prerequisites:
750 gold

Optional:
Argent Tournament Tabard Teleport
Stormwind/Orgrimmar Teleport

NPCs in order:
[npc=29491] Karandonna 15 shirts - Threads of Fate in Dalaran
[npc=29628] Angelique Butler 2 shirts - First to Your Aid in Dalaran
[npc=33853] Broxel Goldgrasp 5 shirts - Argent Tournament
Alliance: [npc=1291] Carla Granger 3 shirts - Stormwind Trade District
Horde: [npc=3317] Ollanus 3 shirts - Orgrimmar

And a guide for the visually inclined! https://www.youtube.com/watch?v=5ynyQ6_dbfA

At the moment (Patch 6.2) there is a total of 30 craftable shirts. To my knowledge Pattern: Bright Yellow Shirt is the only pattern unavailable to Horde player, it can be bought from [npc=2668] in Duswood by Alliance player and sold on the AH. There is also the rare World Drop Pattern: Rich Purple Silk Shirt that is difficult to obtain. The other patterns are fairly easy to get and can drop faster if you have the profession tailoring.

Here's the complete list of reagents to craft all the shirts, considering the tailor learned all the patterns minus Pattern: Rich Purple Silk Shirt. If he did, add 4 Bolt of Silk Cloth or 16 Silk Cloth, 1 Silken Thread and 1 Purple Dye.

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• Raw Materials
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• 32 Bolt of Frostweave or 160 Frostweave Cloth
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• 12 Bolt of Mageweave or 48 Mageweave Cloth
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• 22 Bolt of Silk Cloth or 88 Silk Cloth
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• 13 Bolt of Woolen Cloth or 39 Wool Cloth
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• 9 Bolt of Linen Cloth or 18 Linen Cloth
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• Threads
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• 4 Coarse Thread
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• 7 Fine Thread
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• 4 Silken Thread
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• 7 Heavy Silken Thread
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• Dyes
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• 5 Bleach
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• 7 Red Dye
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• 4 Blue Dye
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• 9 Green Dye
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• 3 Yellow Dye
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• 5 [item=4340]
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• 3 [item=6261]
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• 1 [item=2325]
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• 2 Purple Dye
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• 1 Pink Dye
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Voila, I hope this list helped you.

If you're missing shirts, I found 2 good ways to get them:

1)Tailoring. Tailors can make a lot of shirts. you learn over 10 different patterns for shirts from proffesion trainers alone and none require expensive or rare mats

2)Brawler's guild: Defeating each of the 12 bosses from the Deck Your Collection Achievement will get you one shirt, and you get another for defeating all of them.