WARDROBE ESSENTIALS
The most fundamental part of any wardrobe are the staple items. Staple items can be used in almost any combination, and will generally make you look presentable without having to put too much thought into it. Owning at least one of each of these items will guarantee that you have something to wear for almost all occasions. Buying each of these items will probably take some time, but once you have them, they're incredibly versatile and should last you years if you take care of them. Replace them as necessary, and you have a foundational wardrobe for life.

White Tee-Shirts, Crew Neck
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Maybe the most versatile item on any fashion list, the plain white tee-shirt is an American classic. There are lots of brands selling them, but I personally think Hanes makes the best plain tee-shirt.

Black Tee-Shirts, Crew Neck
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The 'after hours' cousin of the plain white tee-shirt, the plain black tee-shirt serves the same function but projects an entirely different mood. Again, I think Hanes makes the softest and most durable plain tees.

White Oxford Button-Down
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The white Oxford button-down is, for social occasions, the equivalent of a white tee-shirt for casual ones. There's never a wrong time to be wearing a white Oxford button-down shirt. Roll up the sleeves in the summer.

L. Blue Oxford Button-Down
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Light blue is a very popular color for Oxford button-downs, and for good reason: it's the next safest color next to white. It also looks great against dark colors without the fear of having to wear solid white.

Dark Blue Jeans
Buy Tapered on Amazon
Buy Straight on Amazon
Every man needs a pair of dark blue jeans. Dark blue is the most versatile color of jeans, and a good pair will last you forever. Your choice between tapered legs (the cut gets narrower closer to your foot) or straight legged (the same length the whole distance) -- that's usually a matter of preference.

Dark Tan Khakis/Chinos
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There's technically a difference between khakis and chinos, but the difference is minimal, so don't worry about it. You want a pair in a dark tan color as pictured -- versatile like jeans, but a little dressier.

Black Khakis/Chinos
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This will traditionally be referred to as a black pair of 'dress pants'. When paired with a suit jacket (which we'll talk about shortly), this is both professional and still comfortable to wear.

Black Suit Jacket
This is one of two items on the list you'll want to buy in person somewhere (JC Penneys has low-cost, good quality suit jackets) because suit jacket sizing can be tough if you've never bought one. Buy in black.

Oxford Shoes
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There are more modern choices. There are more stylish choices. But a classic pair of Oxfords is the most reliable dress shoe in history, so buy a pair. Actually, buy two: one in brown, one in black.

Socks (Various Colors)
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You should generally have three types of socks: white (goes with jeans), black (goes with black chinos), and tan (goes with tan chinos). Treat yourself and buy Gold Toe ones, they're super comfy.

Navy Blue Suit
The other item you'll want to buy in person, you need a navy blue suit. It's good for almost every formal occasion, and a good suit will last you forever. Don't try to buy online -- go to a suit store like JoS A. Bank or Mens Warehouse for your first suit. You can buy brand names when you have more money. A solid suit (or separates) should run you around/under $200. DO NOT BUY A SHINY SUIT.

Boxer Briefs
Buy on American Eagle
I won't presume to tell you what you should wear around your junk, but if you're over the age of 18, you probably need to be wearing boxer briefs. For my money, American Eagle makes a fine set of undies.

Trainers/Tennis Shoes/Sneakers
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Your choice, although I would recommend you keep them relatively simple looking or in simple colors. I like high top canvas shoes, personally.