Get involved in research!
Northwestern is one of the top universities in the world for research, and it's easier than you think to become a part of a lab. Keep in mind that working closely with a lab can lead to independent study credit, a senior thesis, and letters of recommendation from faculty members. Many undergraduate students even publish papers in professional journals based on their work. It's never too early to start. While some labs require that you've taken statistics or research methods, many labs would be happy to accept enthusiastic students in their first year at Northwestern. Labs sometimes advertise research positions, and most wait for students to approach the lab. So be proactive. Go to the Cog Sci faculty page, and click on a few dozen faculty pages. Read their research descriptions, poke around their lab pages, and pick a few that seem most interesting to you. Read some of their papers to confirm your interest. Write to the professor that directs the lab, and ask for a meeting to discuss research opportunities. When you meet, show that you've done your homework, and ask if you could begin volunteering in the lab. If it turns out that the particular lab is not for you, no one will be upset if you switch to another one. Feel free to ask your Advisor if you have questions about research experiences. And the Cognitive Science Club is a great place to hear about the research experiences of your peers.