I'm just getting back from a tech trade show in Las Vegas where I had to meet dozens of people, some for the first time. Many were contacts who know me only as the person on the receiving end of an email or phone call. Others I've met only a few times. And a few are on a first-name basis; I consider them friends.

One thing I noticed is that there are certain body language cues people send when you first meet them. A few are obvious; others require a bit more perception.

1. Arms open slightly and ready to hug.

It's often hard to tell if you should hug at first. After all, we usually hug people we know really well or haven't seen in a while. Yet, if you have established rapport even over email, it might make perfect sense to greet each other in a warm but brief embrace. Again and again, my contacts who looked like they wanted to greet me that way usually had their arms open slightly, not pinned to their sides.

2. Fake smile or real smile.

This one is a bit more subtle, but you can see it of you look closely. People who smile in a real way do more than just "smile with their eyes"--they look you straight in the eye as if to inform you that the smile is real. (Fake smilers look away quickly.) I noticed another clue. A real smile is an invitation to talk a bit longer--there is genuine interest and a desire to connect a bit more. A fake smile fades quickly. A real smile is always followed up by some genuine questions and signs of interest.

3. The awkward quick handshake.

Be careful with this one. If you shake hands and the other person makes it as quick as possible, it means you might have a conflict with that person or there's some other sign of trouble. Maybe that person doesn't like you or doesn't want to make a deeper connection. A lightening fast handshake says please don't take up any more of my time.

4. The side glance.

Here's another subtle body language clue. If you meet someone and that person immediately looks to the side, it usually means there's a problem in the relationship. Friends greet each other warmly and look each other in the eye. If there's a conflict, the person is too busy, or just doesn't want to spend much time talking, the side glance is a way to look for an escape route.

5. Over-nodding.

In just a few cases, I noticed my contact would start nodding at what I was saying too often. It's another sign that you might be someone who is causing some annoyance or taking up too much time. It's almost as though the frequent nod is a cue to hurry up, to get on with what you're saying, and to give the person something meatier to digest that doesn't require so much nodding.

6. The lean-in move.

More than any other gesture after first meeting someone, I noticed a few people made a point to lean in toward me as an act of showing respect and interest. It was amazing how many people did this one gesture and how it makes you feel like you can show more trust. You can confide in them, because they have leaned in a little to make the job a bit easier.