how to safely reset networking prefs?

Hi, all.
I've had my MBP for about a month and a half now. I had major wifi problems until the new airport update. Now I'm finally able to connect to my university's wifi, but my MBP is still not automatically connecting to my preferred networks at home or at the coffee shop. Is there a safe way I can just reset my network settings and try them from scratch to see if the recent updates have solved the old problems?
Thanks?