Probably the best way to improve your spoken English would be to do a language exchange with someone who wants to learn your native language. That way you can get practice with someone to whom speaking English comes naturally, and in return you can help them.
Another thing you could do, which would be fun, would be to watch television shows in English. You could start out watching English shows with subtitles in your native language, and once you feel you've learned a decent amount of English, watch it without subtitles and see how much you understand. I once met a guy in Spain who spoke nearly perfect English just from watching American television programs.