There's one thing you'll almost certainly need when starting a company: other people's help. The right introduction at the right time can make a world of difference.
How do you get people to help you? If people's interests are aligned to yours, they'll help you out. Those people are called investors. There's another way to get people to help you: make them like you and want to help you.
This ties in with a more general problem that a lot of very technical people face: How can I be a fun person, someone that people want to hang out with?
I was born in France, lived there for seven years, then moved to Casablanca (Morocco) and lived there until I came back to the US for college. Having never spent significant time in the US, I wasn't entirely used to the socializing process when I got here, but I picked up a few simple tips by observing how some of my more popular friends acted. Since I actively did that, I made a mental note of each one. These could generally be summed up as:
"How do I make a good first impression and get people to like me?"
1- Always introduce yourself (with a smile). For some reason, this is really important and labels you as assertive, friendly and outgoing. Make sure you introduce yourself to every member of the group and look them in the eye when shaking their hand. Don't be impolite by interrupting someone, but having said that, there's something very weird about someone who stands around and doesn't introduce themselves.
2- Ask a question. There are a ton of really easy questions you can ask, depending on your social situation. These include general questions, like "Where are you from?" and "What do you do?" as well as more situation-specific ones, like "What company are you with?".
3- Listen to the answer. Keep an open mind and don't assume anything negative. That seems simple, but too many people end up hogging the conversation off the bat by talking about themselves, or judging the other person. However, everybody likes a pleasant person who asks about them, listens, and responds intelligently. They'll usually return the favor by asking about you.
4- Figure out another question to ask based on the previous response. If you can find a way to add some kind of rapport, this is best, like "Oh, you're an engineering major? So am I!" or "You work at Trulia? I have a good friend that works there!". At worst, you should be able to ask for more information: "You go to UCSB? What major are you?"
5- Ask another question. Rinse and repeat.
That's really all there is to it. Besides being generally beneficial to your social life, being a genuinely fun and interesting person has one important benefit to your startup: It makes people want to help you, even if they won't personally benefit from doing so.
In other words, if you get feedback that you're not very "sociable", it is a huge benefit for you to learn to be so. It's not something that everybody is born with, but it is most definitely learnable.
