The “perfect” suit would be custom made for you, so what you’re looking for is the best-fitting, highest-quality suit that you can afford. When you find that suit, it is absolutely worth paying full price and buying all the available pieces (jacket, pants, skirt, dress) – in more than one color, if you can. Here are five characteristics to look for:
Fit – look specifically at areas that are very difficult to tailor, such as how it fits across your shoulders and upper back. Pant length (lengthening or hemming), taking in the waist, hemming or lengthening the sleeves can all be done by any tailor. If you do need extra length, make sure to see how much fabric has been left in the seam. You may want to purchase a suit at a store like Nordstrom, that offers tailoring on-site. That way, a tailor can come evaluate the specific adjustment that might need to be made, pin it, and you can look in the mirror and decide if it’s acceptable before buying. If you usually wear heels, bring a typical/average pair with you so that the length can be adjusted to break at the top of your foot (below the ankle, but not covering your whole foot). Many people wear pants that are too short, and it looks awful. Same thing with sleeve length. Making a fist, the end of the sleeve should fall somewhere between your first and second knuckles . Make sure that there is no pulling or strain on the suit when you sit, bend, close all the buttons, etc.
Style – No mini-skirts, cropped pants, shrunken jackets, funky lapels, flare sleeves/pants, etc. Black, Navy and Dark Gray/Charcoal are your best bets. Certain types of suits look better on certain body types, but generally you are looking for a single-breasted blazer with 2-3 buttons, with the bottom hitting around your hip. If you’re interested in getting both a skirt and pants to wear with the jacket (I recommend it – makes traveling a cinch), make sure that the length is appropriate on the skirt, that it’s a pencil shape (not A-line), not tight, has a slit in the back (should be lightly sewn shut on a new suit). Skirt and pants – secure closure (such as hooks and zipper), not see-through in bright light, not tight in any area (such as the hips) but not loose or baggy.
Fabric – Depends on where you live and work. Don’t get a machine washable or otherwise cheap polyester suit. A wool blend will work 3 or 4 seasons. Sit down for a minute, stand up and see if there are any wrinkles. Walk around and check the movement of the fabric. You probably want lining on the jacket and skirt, and at least partial lining on the pants — though with (potentially itchy) wool, I prefer full lining. If you’re somewhere where it often rains, consider how the fabric reacts to getting wet – e.g. you don’t want silk.
Quality of manufacture – Check for a decent amount of fabric left in the major seams. Look at the stitching — hopefully you’ll find an even, secure stitch at the seams with an inch or two (at least) that could be let out. Look for extra buttons and check that the current ones are fastened securely. Take note of vents and pockets sewn shut – those aren’t going to provide you value once you start wearing the suit, but they are signs of quality manufacture.
Price point – you can get a very decent suit, for example from J. Crew, with a jacket around $250, pants and skirt around $150 each, and a shift dress for around $175. You may want to look into opening a credit card at whatever store you buy the suit from, as they usually offer some % off when you open it. Also consider, as part of the price, the care that will be needed. You won’t usually have to dry clean every time you wear the suit. You can probably get 3-4 wears out of the pants and several more out of the jacket. When you do dry clean, do all of them together so that any fading happens uniformly. That’s why I like having pants, skirt (say each gets 3 wears) and a jacket (let’s say 6 wears), then dry cleaning them all together. You might also want to consider buying from a retailer with a good return policy, like Nordstrom — maybe it gets ruined at the dry cleaner’s, even though they followed the directions on the label. Or maybe you have the tag on the skirt a year from now and find that you’re just always going to wear pants. They’ll take it back.
Keep all this in mind, and you’ll have yourself a look that will last a lifetime, and the confidence that goes with it.