Although I will hopefully be walking you all through a few experimental things during class on the 23rd, this video can and will do a better job than me of walking you through an A/B Test with google's system. This is very good video, and since I don't have two sites set up with Google Web Optimizer, this is a good alternative to me just trying to explain it.
So, the video is about 5minutes long and will go through the whole process of getting your pages set up and how to begin testing. Some of it may seem a little too "techie" but don't be scared off. So take a few minutes and watch this video (at least the first few minutes that shows you how to set up your test).

A/B Experiments with Google Website Optimizer