I would recommend just talking to people in general. I am really not surprised I'm reading in an CS dominate sub. In the few classes I've taken at siebel I've met social butterflies, anti-social ones and arrogant dicks.

As I mentioned, you need exposure to people in general. Practice with talking to people and you'll eventually become comfortable talking to just about anyone.

To calm your nerves I also recommend doing mock interviews with ECS or just career services in general.

One thing that I noticed about myself and it may be true for others is that overthinking and being nervous does not help. When I really tried saying the right thing, I ended up not knowing what to say or saying something stupid and I just ended up looking bad. This is for both at career fairs and when talking to people, particularly the ladies. You know what has given me some success ? Not giving a shit. Just letting things flow. I would be more comfortable and just know what to say. Being more calm around potential employers also makes them less nervous and willing to hear you out and stuff. Also works with the ladies. I've been more "successful" with the ladies by simply not showing your cards at all, by acting like you're not even playing a card game. If you know what I mean.

Also talk about them. Both employers and other people. People love talking about themselves. That allows you to standout in their mind and if you get a second interview you kind of have a foot in the door.

TL:DR

Talk to people. Spark up random conversation from nothing. Literally having a random conversation about anything with a random person, will have you thinking on your feet and overtime it'll just become easy.