(MoneyWatch) Much of the information that we communicate happens non-verbally via subtle signals we put out with our posture, gestures and attitude. It’s no surprise, then, that your success in a job interview depends quite a bit on almost everything except what you actually say. Recently, WiseBread explained the most common body language mistakes people make in interviews — and how to avoid them. Here are the highlights:

Your handshake makes a critical first impression. Your dad probably taught you how to shake hands and his lesson was more important than you know. Make it firm — not body-builder-aggressive and certainly not feeble like a dead fish. Also, be sure your hand is dry, so if you’re perspiring, wipe it off before you meet your interviewer.

Don’t touch your face. People touch their faces instinctively and without conscious thought. But if you want to make a good first impression, you’ll need to be very conscious of where your hands are for the duration of the interview. Keep them well away from your nose and mouth, which can be a turn-off to germophobes. And for everyone else, touching your face is sometimes interpreted as a sign of dishonesty.

Don’t cross your arms. Even if you only know one or two ways to read body language, you probably know this one — crossing your arms is a sign of defensiveness and passive aggressiveness. That’s not the impression you want to convey, so put your hands on the table where they can’t cause you any trouble.

Don’t stare. You probably know that making eye contact is a good thing, right? Well, there’s a difference between positive eye contact and just plain staring. This is one of those things that should be natural, but if you think too hard about it, it is challenging to do in a natural way. The bottom line is that you want to maintain eye contact in moderation, without letting it devolve into uncomfortable staring. At the same time, don’t let your eyes wander around the room as if you’re bored.

Avoid nodding too much. You might think it’s a good idea to nod a lot, either to appear to agree with your interviewer or to imply you’re paying close attention, but the reality is that this can make you come across as sycophantic or spineless. Like eye contact, nod in moderation, and only when it’s clearly appropriate.

Photo courtesy Flickr user Lars Plougmann.