I have about 1,000 tips on this topic, but for the sake of brevity, here are a few:
First, before your visit, spend some time researching the school. Don’t only look and at the school’s website—check out at least two other published/online sources. If possible, also speak to a friend (or family friend, acquaintance, etc.) who either goes to the school or graduated from it within the last decade.
You should also do a virtual/video tour on a site like www.youniversitytv.com before visiting the school. The better informed you are before your visit, the more likely you’ll be to see the aspects of the school that really matter instead of just being wowed by all the big ivy-covered buildings.
Next, on your actual visit, have questions prepared in advance. They should be questions that CANNOT be answered with yes/no or a number/statistic that can be found online. You want unique opinions and personal viewpoints, not canned responses. Ask at least one question during the info session; speak clearly, give your name, and ask away. Do the same with your tour guide.
As for the tour, this is important: Tell your parents to go on a different tour than you do. That way, you won’t be shy about asking the questions YOU want to know, instead of the questions you want your parents to hear you ask. And don’t ask a bunch of questions intended to make you look smart and intellectual—ask questions that matter to you. Your goal is not to impress the tour guide...it's to find out if the school matches you and your interests.
Finally, when you’re on the tour, do some snooping. Think of this as an intelligence mission, where your goal is to figure out what the school is REALLY all about. Look around you (in every nook and cranny), and see which organizations have posters on the wall. If you’re a young Republican and everywhere you go you see rainbow flags and Greenpeace stickers, chances are the school is not the best fit for you.