English 
Tiếng Việt 
Be on time.
This is simply good behavior and is non-negotiable. Do not be late! Being late always equals a bad first impression and is one of the hardest mistakes to recover from
Be mindful of your body language and posture.
Effective body language goes beyond simply standing up straight and having a firm handshake — although those things are definitely important, too. When you’re meeting someone for the first time, keep your posture open — don’t tightly cross your arms or legs, don’t ball your hands into fists, and don’t hunch over in your seat. Lean in when you talk to show you’re actively listening and engaged in the conversation. And don’t be afraid to take up some space at the table, either. If you normally use hand gestures or move around to communicate, don’t hold back. These nonverbal cues can make a powerful subconscious impact, so be aware of your body language and posture during meetings in general, but particularly initial pitches or interviews.
Put your phone away.
If you need to use technology to deliver a presentation, that’s one thing. But unless you’re projecting your computer or tablet screen to present to the entire room, turn off sounds and vibrations on your mobile devices, and put your screens away. Give your complete and undivided attention to the people you’re meeting for the first time to convey your commitment, focus, and let’s face it, your good manners.
That goes for tablets, laptops, and other electronics, too.
Make eye contact.
Focus on the person or people you are speaking with. It’s hard to get to know someone when you’re looking down at a screen, so make an effort to make some eye contact with everyone in the room.
However, keep in mind that eye contact can also backfire, If people aren’t already persuaded or inclined to be on your side, they may focus more on your mouth or any presentation materials you’re showcasing instead of your eyes, making attempts at eye contact a challenge.
Know your audience.
Do your research. If your meeting is planned in advance, you should know plenty about the person or business that you’re meeting with before you arrive. This might mean that you Google the people you’ll be meeting with, the company founders/co-founders, their history, their competition, their main products, and any other relevant info before you walk into the room.
Choose your words wisely.
Words matter even more than you think. Positive and persuasive words and phrases will often open doors and make people feel comfortable in your presence, which can ultimately make them more willing to work with you.
Dress the part.
Regardless of how little you personally care about fashion or style, what you wear matters. While you want to look clean and neat, it’s also important to match or slightly exceed the relative level of formality of the person or business you are meeting with — whether that is business formal, highly casual, or something in between.
“You are your brand, especially if you are a business owner, so making sure that your look communicates your best self is important”
Source from Jacqueline Zenn