First, be sure not to get there too early. Chances are, you will walk in on the class that has not finished from the hour before yours, and then you'll feel stupid for the rest of the semester.
But don't be too late, because you don't want to walk in and flounder as you realize that the only two seats left are quite possibly the most awkward to get to. And yes, everyone does watch as you flounder.
As soon as you sit down, find the clock. If you can't see it, move. You might not thank me now, but you will thank me at 11:46 when you realize that you are actually going to make it through the last four minutes, because you know there are only four left.
Chances are, last names are an excellent indication of a professor's ethnic background and therefore his or her accent. Plan accordingly. (No offense.)
Show up. There is no point in using an absence on what is very likely to be the easiest day of the semester. Plus, then you get a syllabus that can be used to determine the ideal skipping days. For example, every day without EXAM written next to it.