First, I spend the majority of the time having the students go around and introduce themselves. I have them announce their name, hometown, major, the last book they finished, the last music they heard before coming to class, their favorite TV shows past and present, their favorite movie, and what superpower they would like to have.
This creates an atmosphere where it's clear they are valued and interesting. I tell them that the most important thing about this semester is that we can do more together than we can do separately, and that we need every single one of them for that task.
It also means that everyone speaks. That's something I'd like to be true in every single class period.
While they're introducing themselves, I ask them to answer an additional question, one that is related to whatever the reading was for the day or whatever the course topic is (if there haven't been any readings yet). Then I try to ask one or two follow-up questions about their answer. Again, the message is: You will have to explain yourself. There's more to what you're saying than you think. You're going to be asked to go farther.
It's hard not to spend the whole first period on logistics. But the more you can push that outside of classtime, the better off you are. Logistics isn't what the course is about, so spending the whole first day focused on them sets exactly the wrong tone. It says that the arcane mechanics of academia -- grades, percentages, assignments, schedules -- is the most important thing, not your subject or the students' learning.
But on the other hand, clarity of expectations is very, very important. The question you have to ask is whether the best way to help everyone be clear about the expectations is to deliver, in essence, a lecture on the syllabus. Some other ways to pursue that goal might be giving a detailed handout, sending everyone the syllabus by e-mail ahead of the first class and soliciting questions, and starting each class period with a brief reminder of what the next few classes will be about and any assignments or tests coming due during that time (in essence, making logistics an ongoing rather than one-time concern).
Finally, I like to ask the students to set the expectations for the class. Given our mutual goals, what conditions should we endeavor to create in the seminar that will help us achieve them? It's that old elementary school trick of having students develop a list of classroom rules. I find it's important that expectations like civility, full participation, preparation, and fearlessness be spoken out loud -- but not by me.
I'd love to hear from some of the other educators in the readership how they like to handle the first day of class. What tone do you want to set, and how are do your activities make that happen?