In my L1-acquisition class two weeks ago, our professor talked about how only 9% of the speech a baby hears is single words. Everything else is phrases and sentences, onslaughts of words and meaning!
Thus, a baby not only has to learn words and their meanings but also learn to segment lots of sounds INTO words. Doyouwantalittlemoresoupyesyoudoyoucutie. Damn.
When she talked about HOW babies learn to segment words our professor said, and I love it, "babies are little statisticians" because when listening to all the sounds, they start understanding what sound is likely to come after another vs which is not.
After discussing lots of experiments done with babies, our professor added something that I already knew somewhere in my brain but didn't know I know: All this knowledge is helpful when learning an L2 as well:
Listen to natives speaking their language. Original speed. Whatever speaker. Whatever topic.
It is NOT about understanding meaning. It is about learning the rhythm of the language, getting a feeling for its sound, the combination of sounds, the melody and the pronunciation.
Just how babies have to learn to identify single words within waves of sounds, so do adults learning a language. It will help immensely with later (more intentional) listening because you're already used to the sound, can already get into the groove of the languge.
Be as brave as a baby.
You don't even have to pay special attention. Just bathe in the sound of your target language. You'll soak it up without even noticing.