Hi Marian! I decided learning English again (no rush, slow but sure). At this point, i do language exchange with english native speakers. So basically i teach them my native language, and they teach me english. I think this is the most effective way to learn language for intermediate students. Since you said that you are an intermediate, i think the best way achieved "speak english naturally" level is get used to speaking it everyday. The more often you use english, the more you can naturally speak it effortless. I've noticed that my skill is getting better, now i am comfortable in speaking english even tho i still made a lot of mistakes.