As for learning any skill, I think teaching language requires continuous guidance and hand-holding along the way, up until they get it and can do it on their own.
I noticed that guiding students and carefully following up with them on every task is essential to their acquisition of linguistic skills. I think it should be what teachers do most in most of their class time.
In reading/writing, for instance, I make sure I demo note-taking for an article, then I move around to provide help where needed. I also keep an eye on good students and direct them to assist struggling students with the task at hand.
For listening/speaking, I go over what goes into listening for main ideas, then play a small portion of the audio track, then answer it so students can follow my lead. This also serves to support students with lower-linguistic abilities along the way.
I think this approach helps develop a sense of accountability in students, and a critical observation on their own learning–since they get the help and support they need along the way. It may also help reduce dependence on the teacher in the long run.