Go to Italy. That's where I learned Italian. And have a Puerto Rican aunt and take 3 and a half years of Spanish in school. That's how I learned Spanish.
Hahaha....I actually think taking classes might help. And if you know any Spanish speaking brothers or sisters, it always helps to have them teach you a little as well.
I work with a really sweet girl who is from Venezuela, and she spoke ZERO English when she moved here 4 years ago. She still has a very heavy accent, but her English is really good, but she wants to learn more, since she gets confused with some of the words and stuff sometimes. We made an agreement...she's gonna "refresh" my Spanish memory, and I'm gonna help her where she needs it with the English. It's always nice to know people who can help you out. :)