A great suit will feel like a suit of armor – it gives you a whole different level of swagger. Nothing makes me feel more like a confident man than when I’m in a killer suit. If I could, I’d wear a suit all day, everyday, whatever the occasion.

I’ll be sharing my passion for suits through a series of article on suits. This particular article is going to take you through the basics of purchasing a suit. In the next few articles I’ll talk about how to find a suit that fits your body type, talk about how to look for quality, and lots more.

So read on to make sure you know exactly what to look for to ensure that your next suit is one of the best of your life.

1. Know why you're buying a suit.

A suit is kind of a big purchase for a man, so this means you need to know as much as you can about choosing the right one before shopping. Otherwise, you may end up with a suit that won’t look or feel right, and end up in your closet rack for decades without use. The first and foremost question you should ask before a purchase is: "what will be the purpose of the suit?"

2. Deciding what you want.

Do you know if you want one button, two buttons, or three buttons? Do you want a peak lapel? Do you want side vents? What kind of fabric and color do you want?

Overwhelmed or confused? Don’t worry, I’ll guide you through the options.

If this is your first suit, then stick with a wool suit because it can be worn year-round. Cotton suits should only be worn in the spring, summer, and fall. There are even more choices out there like linen suits which are best for summer days or flannel to keep you warm during harsh winter chills. A wool suit will give you the most for your money, so start there.

As a rule, it’s far better to have two great suits than five mediocre ones. Start with a rich midnight blue, a few shades darker than the average navy. This suit will transition beautifully from day to night, and can be worn with both black and dark-brown shoes.

If you have already own a navy suit, you can go for the next most versatile suit color – charcoal. Then move on to your light colors like light brown or khaki. But sometimes these colors won’t compliment your skin tone, and so in that case go for light gray. This is what you can wear in the summertime to dress down a formal look.

A black suit seems like the logical first choice for a young man but it’s actually the least versatile color. But there are times when only black will do, so you should have one nonetheless.

3. Know your exact measurements.

This seems obvious, but make sure you know your exact size, not just the general category of measurements in which you think you fall under. As a matter of fact, you should recheck your size each year. Even if you’ve bought a suit before, don’t keep asking for the same size out of habit. As you gain or lose weight or grow older and gravity takes its toll, your suit size will change.

A suit jacket size is determined by measuring the thickest part of your chest in inches.

1. Begin by measuring just under your armpits and across the chest and over the shoulder blades. Just relax and don’t flex. Make sure you keep the tape measure parallel to the floor when you do this. This will help assure you’re measuring the thickest part of the chest area.

2. You should take an overarm measurement where you place the tape measure over the outside of your arms at your sides and across the thickest part of your chest. Once you have this measurement subtract 7 inches to receive a corresponding chest measurement. Then compare this measurement with the chest measurement and take the larger of the two.

3. Trouser sizes are determined by measuring the waist at the belt line. In most cases, the belt line will be found just on top of your hip bones.

Now that you have all your measurements, on to next step.

4. Checking the fit.

The shoulders of a jacket are crucial to a good fit. Check this area first to determine if the proper suit size has been chosen. (If you stand sideways against a wall and the shoulder pad touches the wall before your arm does, the suit is too big)
Very few men can buy a suit without having the collar raised, lowered, or shortened. Look in a three-way mirror. The jacket collar should hug the back of neck with a half inch of shirt collar showing above it. If the shirt is hidden or there is a buckle of excess jacket fabric, try a different jacket (a tailor can also fix this)
The jacket should not be too long, for example not halfway down your thigh
For the right length: your jacket should be long enough to cover your buttocks. If you have very long legs, however, you may want to wear your jacket slightly longer than your buttocks to make your legs appear shorter and more balanced. If your legs are very short, you’ll want to wear your jacket just above the bottom of your buttocks in order to give the illusion of longer legs.
The sleeves should end at the hinge of your wrist, but leave some room to allow a quarter inch of shirt cuff to show.
You should be able to easily button the jacket without it straining, but there shouldn’t be too much space between the button and your chest — no more than a fist’s worth.
Turn sides and look at the way the pants hang. Legs should fall straight and center evenly over each foot.
Pants should sit more at the hip almost like a pair of jeans, not at the navel
You shouldn’t have to wear a belt (you don’t really need one), and you shouldn’t need suspenders to keep your pants up, it should sit naturally on your waist and stay there
If your waist in nine inches smaller than your jacket size, you’ll need to have your suits custom-made or get a semi-custom suit. You cannot successfully alter pants with that much drop from shoulder to waist with justa nip and tuck.

*Beware of the sales guy who may talk you into buying a suit a size too big because he will say, “Well you want to be comfortable…” or “this suit will last you for the rest of your life, you’ll grow into it!” Uhhh… NO. If you can, take someone with you that you can trust (who’s blunt and honest) to tell you if something looks horrible.