You only have one chance to make a first impression.

And it takes a lot less time for a hiring manager to form their opinion on you. 30% of interviewers make a decision on whether or not to hire you within the first 5 minutes of the interview. And 5% know in less than a minute! That doesn’t give you much time to actually talk about your qualifications for the job. It is, however, enough time for your interview to get a read on your interest in the position and how they feel about you. How exactly? It all comes down to the way you carry yourself: your body language.

Psychology researchers have figured out what positions and actions you should (and shouldn’t!) do to make a solid first impression. Want to master the art of body language? Here are four things you’ll need to keep in mind.

Your Posture

Do: Sit up straight. Roll your shoulders back and lift your chin a bit. It should feel comfortable and relaxed. When talking to the interviewer, lean slightly inward to indicate increased interest. Good posture will give you an air of confidence and the hiring manager will notice your positive body language.

Don’t: Slump. Slouching or leaning back in your seat are both strong indicators of disinterest and boredom.

Your Handshake

Do: Use a firm (not crushing!) shake. Aim for light pressure. And remember to make eye contact and smile! You should always be quick on the draw and try to offer your hand before the interviewer does.

Don’t: Give them a dead fish. Cold, limp, and wet does not a good handshake make. If you suffer from clammy palms (especially when you’re nervous), consider using a hand antiperspirant, a dusting of cornstarch, or alcohol wipes.

Your Facial Expressions

Do: Smile and make eye contact. It’s good to make eye contact when you’re listening to questions and when you begin your response. It’s okay to let your eyes wander naturally while you’re thinking or when you’re in the middle of your answer.

Don’t: Overdo (or under!) it. Making excessive eye contact can comes off as hyper-aggressive and put the interviewer on edge. At the other end of the spectrum, avoiding eye contact makes you seem distracted, distant, and disinterested.

Your Limbs

Do: Feel free to talk with your hands. It’s okay to gesture when you’re talking, especially when it helps you get your point across. It’s also a good way to discharge your nervous energy in the positive way.

Don’t: Cross your arms or fidget. It’s hard to fight the fidgeting, but things like bouncing your legs, clicking your pen, or playing with your hair can come off as unprofessional and put your nerves on full display. Crossing your arms in front of you is often seen as defensive body language and can be misconstrued as a lack of interest in the position.

It may seem like a lot to remember about your body language. Get some practice in with a mock interview. The more preparation you get ahead of time, the more comfortable and relaxed you’ll be in the real interview. And you’ll be ready to make a great first impression to help you ace the interview!