If the opportunity presents itself, go up to people, introduce yourself (if you don't know the person) and make some small talk, Pachter suggests. "One CFO complained to me that one of her staff members came to a meeting, just sat down, and reviewed his slides. He missed a wonderful opportunity to interact with the higher ups in the company."

If everyone doesn't know one another in the meeting room, you need to make introductions. You should do this by starting with the person of the highest rank first, says Pachter.

For example, "Ms. CEO, I would like you to meet Mr. New Hire."

You want to be sufficiently prepared. "Know what the meeting is covering beforehand," she says. And know your part. "Will you be giving a presentation during the meeting or do you need to get some specific information about a new project? Know what questions you want to ask, and what questions people may ask of you, and prepare accordingly," Pachter says.

If you're the one running the meeting, it's imperative that you have a good, strong agenda so that you can stay on track. If you do get off track, you should have a strong facilitator to get you back on track, says Pachter.

If it's a sit-down meeting, you need to adjust your chair so that you're at equal height with everyone else at the table. "Some people don't adjust their chairs, so they end up being the little kid in the meeting," says Pachter.

When people speak in meetings they need to speak loudly enough so that everyone hears what they're saying. "Many men and women, especially women, do not speak loudly enough," Pachter says. "And speaking softly is a subtle nonverbal action that can affect your professionalism."

It's not polite to interrupt others, but in some meetings, you have to interrupt at some point or you won't be heard. Understand the rules so that you can have a productive meeting.

"Say what you need to say in as few words as necessary," Pachter suggests. "Don't keep repeating yourself or giving unnecessary information."

A lot of people keep their phones on the table during meetings, says Pachter. Don't do this. Even if you aren't looking at your phone, it can get distracting if it starts lighting up or making noises.

"Put it in your pocket, keep it on vibrate, and leave the room if you have to take the call or return a text," says Pachter. "It's really, really rude to be texting during a meeting."

Unless it's a breakfast, lunch, or dinner meeting — avoid eating at the table. "You can make noise or give off smells" that are disruptive, she says. But if you need to eat in the meeting, for whatever reason, it needs to be okay with everyone in the room.

This is especially true if you were drinking or eating during the meeting. You need to clean up after yourself and leave things the way you found them, says Pachter. It’s rude, and not professional, to leave a mess.

Ask your questions at the appropriate time. Do not be the person who starts "asking questions and adding stuff that doesn't need to be added" when everyone's getting ready to go, warns Pachter. You don’t want to be "that" guy.

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