Hm... I think, paradoxically, speaking a language doesn't mean pronouncing it well. It might, if you simultaneousy set to imitate native speakers you communicate with, like children do. But you've probably met or in some other way heard immigrants who had spent a decade or more in America and still spoke English with a terrible accent... Well, take Arnold Schwarzenegger, although he's a bit of a special case.

Anyway, I think I've already mentioned that I practice pronunciation by recording myself reading - mostly news articles... I suppose I'm able to get away with that because I've listened to enough of those languages to be able to tell when my pronunciation is wrong. Although I sometimes consult forvo to make sure.

I can't actually be certain of the efficacy of this method, because I haven't had a native speaker check my efforts, but I know that I do make progress, discovering new ways to approach the native sound every time... in other words, finding new mistakes in my pronunciation, which might not sound so encouraging, but I consider that a sign of becoming more nuanced in listening to the language.