The 7 worst body language mistakes job seekers make

People tend to show their dominating personality by gripping the interviewer's hand and palming it down, but this tells the interviewer that you need to feel powerful, Reiman explains. "Instead, the handshake should be more natural: thumbs in the upward position and two to three pumps up and down."

As the applicant, you should always wait for the interviewer to extend their hand first, she adds.

There is nothing worse than shaking hands with someone who has clammy palms. "If this is you, go into the bathroom and rinse your wrists under cold water for a good minute," she suggests. "This will give you dry palms for roughly 10 minutes so your first handshake is a strong and powerful one — not sweaty and insecure."

"Make sure you offer the appropriate amount of eye contact," Reiman says. "If you don't, the interviewer will assume you are either insecure, don't have an appropriate answer for the question being asked, or are being deceptive. Does that mean it's true? No, but perception is everything in a job interview."

Playing with your hair, touching your face, or any other kind of fidgeting can be a major distraction for your interviewer. It also demonstrates a lack of power, Reiman says. "When we touch our faces or hair, it is because we need self soothing."

Is that the message you want to send to your interviewer?

You don't want to be shifting in your chair or crossing and uncrossing your legs, she says. This may tell the interviewer that you're bored. Instead, demonstrate interest by leaning slightly forward, tilting your head, and nodding on occasion.

Reiman says smiling demonstrates confidence, openness, warmth, and energy.

"It also sets off the mirror neurons in your listener, instructing them to smile back. Without the smile, an individual is often seen as grim or aloof," she concludes.