American English has many expressions related to clothes. Two of the more common ones are: “Dress for the job you want, not for the job you have”; and, simply, “Dress for success.”

A professional stylist takes these ideas a bit farther. She says that our clothes can influence how we feel, our confidence, even our ability to do a job. And new research supports her claim.

Tara Luizzi is a personal stylist in Washington, D.C. Through her company, Tara Styles DC, she teaches her clients to find the clothing styles that work best for their bodies, careers and lifestyles.

Luizzi says that, like it or not, other people size us up by the way we look. In other words, they make a judgment about us before we even speak. And part of what they are considering is what we choose to wear.

“My feeling is you don’t have a second chance to make a great first impression. So, I think it is very important to have a look that’s pulled-together and conveys who you are and your status of life, I guess.”

Here, “pulled-together” means that someone’s appearance is well-thought out. Luizi says she feels this is very important. She notes that clothes are especially important in creating the professional image you want to convey.

“No matter what, you should try to always walk out the door looking pulled-together -- if it be on the weekend or if it be during the work week. People take you more seriously when you are pulled-together and dress to a certain level.”

But choosing the right clothes is not just about impressing others. A recent study suggests that people who are dressed more formally perform better at some work tasks.

The co-authors of the study are psychologists Michael Kraus of the University of Illinois, Urbana-Champaign and Wendy Berry Mendes of the University of California, San Francisco.

Kraus and Mendes compared more than 100 men from diverse economic and racial backgrounds. They asked some to dress in business suits. They asked others to wear sweatpants, t-shirts and flip-flops.

Then the researchers asked the participants to do several work tasks.

One task involved making a business deal. Those wearing suits demanded more in their business deal. The participants dressed more casually were more willing to concede, or give up.

The other task was to use big picture thinking to solve a problem. The men in suits were more able to think about the big picture, the way a boss would.

Those in casual clothes focused more on smaller details of the problem. This type of thinking is what you would expect from someone in a lower position.

Kraus and Mendes published their findings in the Journal of Experimental Psychology.

Stylist Tara Luizzi says, to her, the study makes perfect sense. She compares clothing to armor, what a warrior puts on for protection in battle.

”When you feel confident in yourself, I think you have a better day. So, I use clothing as the armor to the world. So, let’s say you’re having a horrible day or you’re nervous about your presentation or maybe the big meeting, If you dress in something you love or you feel great in, you’re going to walk in with more confidence.”

In her job, Luizzi sees how the right outfit can change the way a person feels. When she chooses clothing for her clients that look good great on them, their backs straighten. They stand taller. And they start smiling.

“They just feel so much better about themselves. So, my goal with every client is to try to get that out of a person. I don’t want anything in your wardrobe that makes you not happy. It should be happiness.”

Luizzi says that, in general, people have a powerful emotional connection to their clothes. The intensity of people’s feelings about clothes and their appearance has surprised Luizzi.

“Many people have an emotional connection to their clothing. You know, for a lot of my clients, there's an emotional level to it in that maybe they had a bad experience when they were younger shopping."

"Maybe they were overweight and they’ve lost weight. Or maybe when they were young they couldn’t afford the clothes they can afford now."

"I’ve been in dressing rooms and closets and tears have been shed because it does bring up an emotional thing. And it was something I wasn’t expecting when I first started this business.”

For people going back to work or preparing for a job interview, Luizzi has some advice for them.

Research the environment of the job. Is it a casual working environment or formal? Is it creative or conservative? For a man, wearing a suit is not always the right choice. If the job is creative and casual, a suit might look out of place, or strange.

When going on a job interview, wear something new or at least newer.
Make sure your shoes are clean and polished.

For women, don’t wear too much make up, perfume or jewelry.
And for your general, everyday wardrobe, Luizzi advises to keep it simple.

She helps her clients create what she calls a "capsule wardrobe." This is a small collection of well-made pieces of clothing that the client loves.

Luizzi says a couple of expressions really represent her attitude toward creating a wardrobe: “less is more," “quality not quantity,” and "go-to."

“Less is more. And I'm more about quality than quantity. So, I would rather have people have a smaller wardrobe made up of the things they love, that fit them correctly and that, you know, are higher quality. And that’s their go-to … the capsule wardrobe.”