when you learn a new language. how do you improve your speaking skills while you don't know any native speaker of that language?
(I assume you mean conversing skills, as speaking skills don't really require a native speaker.)
After learning the basics on my own, I use skype when I'm ready to converse.
You really need to find someone to speak to. I mean you can practice speaking exercises and all that but speaking to a live person really enforces what you learned like nothing else.
I believe practicing with someone is invaluable in learning foreign languages. Perhaps you could find non-native speakers to chat with. Obviously they might not correct your mistakes, but this could be a way to start. Besides, having some soulmates who support you in your struggling is a nice thing.