The way I learned Spanish was through high school. I took it for four years, studied, did my homework and practiced it when I could. The best place to practice Spanish is with a native speaker.

Why?

Native speakers have a rhythm you are not used to hearing in school. They speak a little faster, and their words flow a little more together. So you are forced to stop and re-think and re-hear their speech pattern. This is actually a good thing, although a struggle at first. It causes your brain to pay more attention to how things are pronounced and sound when you actually visit a country with native speakers. So you might as well get as much practie out of it as you can.

I vouch this for any language. Learn how real people say it. It's the same reason why parents are encouraged to speak in regular voice to their babies vs. the "goo goo ga ga" talk with the misprocunciations. The child is learning and, of course, still getting used to pronunciation, but if you perpetuate the "goo goo ga ga" speak, they're going to hear it wrong and learn it wrong. The same applies for learning another language.

My mother is from Thailand, and I can communicate with her, but it's not necessarily "proper" Thai. She uses slang, short cuts, anglo-cised words and phrases that don't carry over into Thai society, necessarily. I have on occasion spoken to people in Thailand who kind of laugh and politley tell me, "That's not what we say around here." So it's a learning curve, but a good one.

A lot of people tend to emphasize memorizing vocabulary when speaking another language, but it's really about concepts. I could have a conversation in Thai with a Thai person about our van breaking down on the road because of a flat tire, but I suddenly forget the word for "tire". So I describe it by communicating, "and then the -- how do you say it in Thai? The thing under the car that goes round and round -- went flat." Then they reply, "Oh, you mean the tire (the word for it in that language)".

Bottom line--practice with native speakers as often as you can. The more you do it, the better you learn and the more proficient communicator you will be.