When you're doing a job interview, whether virtual or in person, you'll want to follow the appropriate etiquette.

"You want to make sure that you're making good eye contact," says Emily Levine, executive vice president at recruitment firm Career Group Companies, "that you're reading the room in terms of when it's appropriate to speak, when it's appropriate and time to ask questions."

Levine has interviewed "thousands and thousands of people" in her career, she says, often for A-list celebrities looking for personal assistants or chiefs of staff.

Here are Levine's best tips for avoiding her top red flags in a job interview.

Don't show up too early

To begin with, you'll want to make sure you arrive at an appropriate time, especially if you're there in person.

Arrive too late, and you risk missing part of your interview, wasting your interviewers' time and making a bad impression. But "if you show up too early, it's also too eager and might make the interviewer feel rushed," says Levine. Ten minutes early is the "perfect" time to walk into your interviewer's office.

"I recommend making sure that you are parked 15 to 20 minutes early in the building" as a precaution, says Levine. That will ensure you have enough time to find the suite or office number but that you're not there long before the interview starts.

Present yourself as professionally as possible

Presentation is also key.

If you're online or in person, "don't chew gum, don't have your sunglasses on your head" during the interview, says Levine. These are too casual and unprofessional.

If you're in person only, make sure you don't come in "smelling like cigarette smoke or wearing too much perfume," she says. A lot of people are sensitive to smell and you want to make sure it's not uncomfortable for them to be in the same room.

You want to leave "an impression based on your experience, not the way that you're dressed or you smell," she says.

Don't divulge confidential information

Finally, regardless of your professional past, be strategic about how you talk about it.  

Avoid bad-mouthing previous employers, for example, or "divulging too much information that's proprietary or confidential," says Levine. Especially in her line of work, some of her clients make their employees sign non-disclosure agreements. When candidates tell her they've signed an NDA but still proceed to divulge confidential information about a previous employer, it's a red flag.

Regardless of how private your employer was, spilling secrets gives the impression that if your interviewer hired you and shared proprietary information, in the future, you "would most likely do the same" with them, says Levine.

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